[CLOSED] Dabs Lotto Number 1. Winner! Congratulations to 1MYJkAp...

[Dabs]

2013-05-24 UPDATE: Dabs Lotto Number 2 is here-> https://bitcointalk.org/index.php?topic=212855
2013-05-21 UPDATE: Dabs Lotto Number 1 has a winner! Congratulations to 1MYJkAp...

Hi,

I've decided to host and organize a simple raffle. But it is not free. So therefore I am posting this in the Gambling section.

Dabs Raffle Number 1

a raffle style lottery using bitcoins
transparent
play instantly - no registration required
cheat-proof
95% payout of funds
provably fair
cryptographically verifiable
no blockchain spam


How to Play:

Send any multiple of 0.01 to:

1K7TmkJ5MT95nGbVgDxp1Vi8LT6ZBEYEcF


using compatible bitcoin wallet software, where you can prove ownership of the sending address.

See list below.

Code: (Bitcoin Address)

1K7TmkJ5MT95nGbVgDxp1Vi8LT6ZBEYEcF

Code: (Message)

I am Dabs on bitcointalk.org and this is my personal raffle, lottery or game.

Code: (Signature)

IGmnBYcfwDVb83ZzJPJ59DzZaF8B4hhrac9P/vCiOhIktxftu1sgaoX6U/0/POhfOufBtI+4vesoFbjA1EY9P7s=

You can opt to do one of two things after sending the bitcoins:

1. That's it. You are effectively anonymous. If you win, you get your winnings sent to the address you sent your bet from. If you sent from more than one address, the winnings will be sent to one of them.

2. Post here your transaction ID, your sending address, and sign it (using the message signing feature of bitcoin.)

If 1. Then just wait to see if you win.
If 2. If you win, you can post here if you want your winnings sent to another bitcoin address. You must prove ownership by signing both messages.

All payments received prior to deadline is part of the raffle.

Deadline is May 20, 2013 or the first block after that time.

If it is not listed here assume it is not compatible.
Note: Any method that sends BTC using only your own private keys is compatible.

Bitcoin
Electrum
Armory
BitcoinJ
MultiBit
Blockchain.info
Blockchain (Android)
BitcoinSpinner (Android)
Bitcoin Wallet (Android)
Blockchain (iOS)

Will NOT work: Any Shared Wallets such as BitPay, Mt.Gox, localbitcoins.
If you are unsure, sending some BTC to Blockchain.info, then buying the tickets with it, is quick and easy.


About Dabs' Raffle:

This is a raffle style lottery. Therefore, the odds of winning scale with the jackpot size compared to ticket price. No matter how small or big the jackpot, the price of each ticket, is a good deal. 95% of tickets sales go to the winner.

By using bitcoins for a lottery a couple unique features are now possible:

• the players identities are unknown but all the tickets are known
• every ticket purchased can be viewed by everyone along with the senders bitcoin address
• each ticket is permanent and can't be altered because it is stored inside the blockchain
• the pot size can not be faked as anyone can check the lottery address and verify it

The players can be known too. Just post here.

Most importantly, it's impossible to manipulate who wins or fake a payment to the wrong person because:

• each ticket has a unique number that is permanent (transaction hash)
• using some block data and hashing with SHA-256
• the transaction hashes stored in the blockchain are then used to calculate the winner in an impossible to predict way
• a secret known only by me is hashed and published so I can not change the secret later
• the secret is then published after the deadline
• the winnings are then sent to the EXACT same address that bought the ticket or to an address that you choose.

All of this can be monitored and verified by anyone and is recorded in the blockchain.

Good Luck.

After the draw all tickets and their hashes will be posted along with the winner.

How I will compute your hashes:
1. Get your transaction id, appending a 10 digit number depending on how much you sent.
2. use my secret
3. hash them together as one string
4. sort the hashes

The secret is secret until I publish it, but the SHA-256 hash of that string is:
dcc369beedaba36b1f1b794b75228c16daa2adb9d8fb60b5cd2a3f68ea96a2da

If you send exactly 0.01 then I will take your transaction ID and append a 10 digit number as 0000000000 with leading zeros.

If you send more than 0.01 then I will take your transaction ID and append a 10 digit number for every multiple of 0.01 with leading zeros, starting at 0000000001.

Every fraction of bitcoins less than 0.01 will not be counted, so if you send 0.0199 I will consider that as still 1 bet. The rest, I will consider as a donation. Thank you.

Examples:

If you send 0.01, then your transaction id is used like this:
sha256("txid0000000000secret")

If you send 0.05, then your transaction id is used like this:
sha256("txid0000000000secret")
sha256("txid0000000001secret")
sha256("txid0000000002secret")
sha256("txid0000000003secret")
sha256("txid0000000004secret")

Where:
txid = transaction id in hex as it appears in bitcoin-qt or blockchain
0000000000 = your first ticket or only ticket
0000000001 = your next ticket.
secret = my secret, no one else knows until after

Ten (10) digits is used just in case someone sends me a large number of coins.

The winner is the hash with the lowest value.

I will then send 95% of the total pot to the winner.

Some Questions:

Why am I keeping 5%?

1. This is my game. If you don't like the rules, don't play.
2. I am going to do all the hashing manually. If I get more than a few hundred bets, I will have to figure out a way to do this with software.
3. If 100 people play and send 0.01, the winner gets 0.95 and I keep 0.05, I think that is fair enough for my efforts.
4. If 1000 people play and send 0.01, the winner gets 9.5 and I keep 0.5, I think that is fair enough considering I might be doing this manually.
5. If 10,000 people play, I'm going to have to code something or someone else can donate the source for this.

Although I said you can send from multiple addresses, as that's how bitcoin works, I would prefer you send your bet from a single address.

Will you use escrow?

I could. Do you have someone in mind? His fees will have to be deducted from the total. I don't want to bug any of them and I'm trying to be my own escrow, but I understand if there is any hesitation.

For reference, I am doing a group buy for ASIC chips and the address used there is holding at least 30 BTC (could be more by now.) I won't update this post to reflect the current amount, you can go check there for yourself.

Will you make a website for this?

Not any time soon. There is no need for a website really. Anyone and everyone can verify the winning ticket.

How long is the secret?

It is alphanumeric 64 characters long. The SHA-256 hash of that string is:
dcc369beedaba36b1f1b794b75228c16daa2adb9d8fb60b5cd2a3f68ea96a2da

I will publish the secret after the deadline is over. Then actually, anyone else can compute who is the winner.

You can compute that the secret and the hash is the same, the length prevents anyone else from attempting to cheat, including myself.

What if you change the secret or the rules?

Someone else quote me. Then I can't change the secret, the hash, or the rules. The most I could do is cancel the game and refund everyone their bets.

Why is the deadline May 20?

Because I don't want it too long so I thought about a week from now is just right. Maybe the next one, depending on how this turns out.

Is the deadline really May 20?

Well, if you manage to put a bet in 5 minutes after midnight, I might consider it. I am doing this manually. I will just post here that the game is over or the deadline has been met, and anything sent in after that is not included in the game. And I am probably in a different time zone from you, so yeah, give or take 24 hours. It's over when I say it's over.

What if two tickets get the exact same hash result? (a collision)

In the rare case that happens, I will split the winnings among the two winners.

What if three?

I'll divide it as well. Extremely rare, but it might happen.

Is this a scam?

Don't bug me. Don't play. I am doing this as an experiment, and like I said I already am publicly holding at least 30 BTC of other people's money (eventually, that will reach more than 800 BTC if it ever completes.)

Will there be a game number two?

Maybe. I don't know. Depends on how much work it is to run this, or if I can figure out a way to automate it (I'm sure it can be, but my brain isn't working now.)


Ok, so.... the game starts ... now.


Dabs

[Dabs]

Reserved. I'm not sure why. But I'm reserving this post anyway.

[Otoh]

Quoting the OP as requested.

Hi,

I've decided to host and organize a simple raffle. But it is not free. So therefore I am posting this in the Gambling section.

Dabs Raffle Number 1

a raffle style lottery using bitcoins
transparent
play instantly - no registration required
cheat-proof
95% payout of funds
provably fair
cryptographically verifiable
no blockchain spam


How to Play:

Send any multiple of 0.01 to:

1K7TmkJ5MT95nGbVgDxp1Vi8LT6ZBEYEcF


using compatible bitcoin wallet software, where you can prove ownership of the sending address.

See list below.

Code: (Bitcoin Address)

1K7TmkJ5MT95nGbVgDxp1Vi8LT6ZBEYEcF

Code: (Message)

I am Dabs on bitcointalk.org and this is my personal raffle, lottery or game.

Code: (Signature)

IGmnBYcfwDVb83ZzJPJ59DzZaF8B4hhrac9P/vCiOhIktxftu1sgaoX6U/0/POhfOufBtI+4vesoFbjA1EY9P7s=

You can opt to do one of two things after sending the bitcoins:

1. That's it. You are effectively anonymous. If you win, you get your winnings sent to the address you sent your bet from. If you sent from more than one address, the winnings will be sent to one of them.

2. Post here your transaction ID, your sending address, and sign it (using the message signing feature of bitcoin.)

If 1. Then just wait to see if you win.
If 2. If you win, you can post here if you want your winnings sent to another bitcoin address. You must prove ownership by signing both messages.

All payments received prior to deadline is part of the raffle.

Deadline is May 20, 2013 or the first block after that time.

If it is not listed here assume it is not compatible.
Note: Any method that sends BTC using only your own private keys is compatible.

Bitcoin
Electrum
Armory
BitcoinJ
MultiBit
Blockchain.info
Blockchain (Android)
BitcoinSpinner (Android)
Bitcoin Wallet (Android)
Blockchain (iOS)

Will NOT work: Any Shared Wallets such as BitPay, Mt.Gox, localbitcoins.
If you are unsure, sending some BTC to Blockchain.info, then buying the tickets with it, is quick and easy.


About Dabs' Raffle:

This is a raffle style lottery. Therefore, the odds of winning scale with the jackpot size compared to ticket price. No matter how small or big the jackpot, the price of each ticket, is a good deal. 95% of tickets sales go to the winner.

By using bitcoins for a lottery a couple unique features are now possible:

• the players identities are unknown but all the tickets are known
• every ticket purchased can be viewed by everyone along with the senders bitcoin address
• each ticket is permanent and can't be altered because it is stored inside the blockchain
• the pot size can not be faked as anyone can check the lottery address and verify it

The players can be known too. Just post here.

Most importantly, it's impossible to manipulate who wins or fake a payment to the wrong person because:

• each ticket has a unique number that is permanent (transaction hash)
• using some block data and hashing with SHA-256
• the transaction hashes stored in the blockchain are then used to calculate the winner in an impossible to predict way
• a secret known only by me is hashed and published so I can not change the secret later
• the secret is then published after the deadline
• the winnings are then sent to the EXACT same address that bought the ticket or to an address that you choose.

All of this can be monitored and verified by anyone and is recorded in the blockchain.

Good Luck.

After the draw all tickets and their hashes will be posted along with the winner.

How I will compute your hashes:
1. Get your transaction id, appending a 10 digit number depending on how much you sent.
2. use my secret
3. hash them together as one string
4. sort the hashes

The secret is secret until I publish it, but the SHA-256 hash of that string is:
dcc369beedaba36b1f1b794b75228c16daa2adb9d8fb60b5cd2a3f68ea96a2da

If you send exactly 0.01 then I will take your transaction ID and append a 10 digit number as 0000000000 with leading zeros.

If you send more than 0.01 then I will take your transaction ID and append a 10 digit number for every multiple of 0.01 with leading zeros, starting at 0000000001.

Every fraction of bitcoins less than 0.01 will not be counted, so if you send 0.0199 I will consider that as still 1 bet. The rest, I will consider as a donation. Thank you.

Examples:

If you send 0.01, then your transaction id is used like this:
sha256("txid0000000000secret")

If you send 0.05, then your transaction id is used like this:
sha256("txid0000000000secret")
sha256("txid0000000001secret")
sha256("txid0000000002secret")
sha256("txid0000000003secret")
sha256("txid0000000004secret")

Where:
txid = transaction id in hex as it appears in bitcoin-qt or blockchain
0000000000 = your first ticket or only ticket
0000000001 = your next ticket.
secret = my secret, no one else knows until after

Ten (10) digits is used just in case someone sends me a large number of coins.

The winner is the hash with the lowest value.

I will then send 95% of the total pot to the winner.

Some Questions:

Why am I keeping 5%?

1. This is my game. If you don't like the rules, don't play.
2. I am going to do all the hashing manually. If I get more than a few hundred bets, I will have to figure out a way to do this with software.
3. If 100 people play and send 0.01, the winner gets 0.95 and I keep 0.05, I think that is fair enough for my efforts.
4. If 1000 people play and send 0.01, the winner gets 9.5 and I keep 0.5, I think that is fair enough considering I might be doing this manually.
5. If 10,000 people play, I'm going to have to code something or someone else can donate the source for this.

Although I said you can send from multiple addresses, as that's how bitcoin works, I would prefer you send your bet from a single address.

Will you use escrow?

I could. Do you have someone in mind? His fees will have to be deducted from the total. I don't want to bug any of them and I'm trying to be my own escrow, but I understand if there is any hesitation.

For reference, I am doing a group buy for ASIC chips and the address used there is holding at least 30 BTC (could be more by now.) I won't update this post to reflect the current amount, you can go check there for yourself.

Will you make a website for this?

Not any time soon. There is no need for a website really. Anyone and everyone can verify the winning ticket.

How long is the secret?

It is alphanumeric 64 characters long. The SHA-256 hash of that string is:
dcc369beedaba36b1f1b794b75228c16daa2adb9d8fb60b5cd2a3f68ea96a2da

I will publish the secret after the deadline is over. Then actually, anyone else can compute who is the winner.

You can compute that the secret and the hash is the same, the length prevents anyone else from attempting to cheat, including myself.

What if you change the secret or the rules?

Someone else quote me. Then I can't change the secret, the hash, or the rules. The most I could do is cancel the game and refund everyone their bets.

Why is the deadline May 20?

Because I don't want it too long so I thought about a week from now is just right. Maybe the next one, depending on how this turns out.

Is the deadline really May 20?

Well, if you manage to put a bet in 5 minutes after midnight, I might consider it. I am doing this manually. I will just post here that the game is over or the deadline has been met, and anything sent in after that is not included in the game. And I am probably in a different time zone from you, so yeah, give or take 24 hours. It's over when I say it's over.

What if two tickets get the exact same hash result? (a collision)

In the rare case that happens, I will split the winnings among the two winners.

What if three?

I'll divide it as well. Extremely rare, but it might happen.

Is this a scam?

Don't bug me. Don't play. I am doing this as an experiment, and like I said I already am publicly holding at least 30 BTC of other people's money (eventually, that will reach more than 800 BTC if it ever completes.)

Will there be a game number two?

Maybe. I don't know. Depends on how much work it is to run this, or if I can figure out a way to automate it (I'm sure it can be, but my brain isn't working now.)


Ok, so.... the game starts ... now.


Dabs

[Dabs]

I'm not changing the rules for this draw. However, people might have ideas about the next one (if I do another one.) Here are a few of my own:

1. Have more than one winner. The pot gets divided into 1st place, 2nd place and 3rd place. Or some variation. This is easily done by sorting the final hashes. The one on top (lowest value) gets the jackpot. Also maybe 1 first place, 3 2nd place, and 5 3rd place that gets maybe 60%, 20%, 5% or something like that. Maybe the 3rd place is just simply a win-back, or you get back what you put in (on a per ticket basis). So you don't lose your 0.01, and can then bet again the next draw or just keep it.

2. Fully automate this game and have it run every 2 or 3 days, or every week. I'm thinking about this. After a draw, there is a time frame before computing the hashes and revealing the secret and the winner(s), then sending the pot to the winner. (For now, the sending of bitcoins is done with manual intervention, I don't want a "server" to have access to the pot.)

3. Minimum initial pot. I'd need some sort of "investors" if we start anywhere above zero. The way this works right now, any investors have the same chance of winning as the number of tickets worth they have bought. Or if the pot has not reached a minimum, no winners are declared and the next draw date is announced. Just like normal lotteries that don't have winners, the pot just gets bigger.

4. Use third party random numbers such as from real life lotteries, or the hash of a news headline. I don't know why but it complicates things needlessly.

5. Escrow with a third party really really trusted member. Escrow of another secret with another really really trusted member (hash is public, secret is revealed later.) As much as possible I don't want to bother anyone else, so any responsibility is solely on me. This is sort of related to point 4 above. It complicates things needlessly. So I am actually averse to both points now. But I'm throwing out the idea anyway.

6. Different games with different ticket prices. In my country, we have such things as EZ Lotto, Super Lotto, Mega Lotto, Grand Lotto, with prices approximately 0.01, 0.05, 0.10 and 0.20. The odds are adjusted and the initial jackpots are different. These are optional in a bitcoin version, but the ticket prices indirectly determine the size of the jackpot. Bigger tickets means bigger winnings most of the time, for the same number of tickets bought.

And just to clarify something, I said this about a different game, but it applies here as well:

There is always a winner because the first hash after sorting is the winner. So the winner is not based on what numbers you pick in the Mega Millions, or what address you use, but rather, each ticket is essentially a computer generated lucky pick, or quick pick, or you can't pick it, it just computes it based on your bitcoin transaction hash or transaction ID.

Ideas, questions, comments are welcome. And of course, play the game.

Check out the current pot at this address:
https://blockchain.info/address/1K7TmkJ5MT95nGbVgDxp1Vi8LT6ZBEYEcF

[Dabs]

Bump. Or at least comment. What did people like about previous raffle types? or dissect my rules to see if there are any holes or flaws or something you'd like to implement or change.

[BRules]

As you're asking, the problem is that PeerBet do raffles exactly like you're offering in an automatic way and do not charge for it.

[Dabs]

I believe PeerBet sets the number of tickets or something. Mine is variable, so it depends on the number of tickets bought, (or the number of people who play).

I will have to check out that site and see what I am doing is the same or different.

[Dabs]

As of right now, PeerBet does not yet allow a time-based game with variable number of tickets, so the pot gets bigger as more players buy tickets. If you make a game on PeerBet for 10 tickets, that costs 1 BTC each, then the jackpot is limited to 10 BTC, it can't get bigger, and it won't end on a specific date.

They might actually include that feature in the future, but I'm still going to try to run this one I made.

[Dabs]

Hey, someone bet bought one ticket. Cool. Deadline is May 20, 2013, give or take a few hours.

*edit* My statement seemed weird, so I edited it to reflect what I meant, that I wasn't asking someone to bet, but that someone did get a ticket already.

[Dabs]

If ever this takes off, (or even if it doesn't), can I use bitlotto.country  or .info ? (because obviously bitlotto.com is taken.) Or is that bad form? The reason I did not come up with a competitor to the original bitlotto was out of delicadeza. (This is a spanish word that means being gentle or sensitivity something, as opposed to being callous or shameless.) Or you could think of it, as out of respect for the original operator.

But, since he's AWOL and disappeared... I am about 2 or 3 years behind in the game since that started in 2011. So I can pick up a thing or two about how it operated before, and how I want this new one to operate.

https://blockchain.info/address/1K7TmkJ5MT95nGbVgDxp1Vi8LT6ZBEYEcF

There is one bet now. If another person puts in their bet, the odds are 1 in 2 (or 50%) chance of winning the jackpot.

[Dabs]

I'd like to solicit feedback from other users, and others more experienced with this. I have thought of creating a website that has a local bitcoind or alternatively monitoring blockexplorer or blockchain, then dynamically updating an ongoing list of tickets for all to see. It's not necessary, but it's just nice to see.

Security should not be an issue because the server will not have access to the private key or the secret.

The low-tech method of verifying and determining the winner still works of course. It has to be at least easy enough for an individual to manually check their particular ticket, and the winning ticket as well.

Still about 2 or 3 days left to go for this round / draw.

[Dabs]

Just a few more hours, then I will determine the winner.

I will add a couple of rules in favor of the players:
1. If there are less than 100 tickets sold, 100% of the jackpot goes to the winner, less transaction fees.
2. If there is only 1 ticket sold, 100% of the jackpot goes to the winner, I will shoulder the transaction fee of 0.0005.

For the first one, I am going to make a sliding scale based on powers of 10, starting from 100%, and going one percent down, all the way up to 10 million bitcoins worth (just in case.)

Then for future draws, I am also going to make something for discounted bulk tickets, like if you are buying 100 tickets or 200 tickets is a 5% or 10% off. I'm still figuring this out. Let me know what you guys think.

[Dabs]

Round 1 over.

The secret is
hPwnC7wa1Z80BAcIzWd1fmTmb6JAS42j5rLAXVCLC6DUAW43MWZpmpoYA3L5yj3E

the sha-256 hash of that is
dcc369beedaba36b1f1b794b75228c16daa2adb9d8fb60b5cd2a3f68ea96a2da

There was only one transaction
2d5ab5db0946875132a8372ee48403813a3cf4a79a7d630bcc700e37ccfc2d9b

for one ticket
0000000000

coming from bitcoin address
1MYJkApNQDaBDVA6cCfS1TvFKicH7ZZ5jL

The string to hash is therefore

Code:

2d5ab5db0946875132a8372ee48403813a3cf4a79a7d630bcc700e37ccfc2d9b0000000000hPwnC7wa1Z80BAcIzWd1fmTmb6JAS42j5rLAXVCLC6DUAW43MWZpmpoYA3L5yj3E

The result is
68fe5e0813a36b8e1f6c2244ea303bf33210b2fe9f3ea813ff22c9108d556f4f

Sorting the list (well, there is no list) so the winner is
1MYJkApNQDaBDVA6cCfS1TvFKicH7ZZ5jL

Congratulations.

Per the updated and amended rules of this round, since you are the only player, you get the entire jackpot.

Status: 1/unconfirmed, broadcast through 16 nodes
Date: 2013-05-21 15:43
To: Dabs Lotto 1 Winner 1MYJkApNQDaBDVA6cCfS1TvFKicH7ZZ5jL
Debit: -0.01 BTC
Net amount: -0.01 BTC
Transaction ID: 760f7c1a9dccc46c940d2ad49b0adadda89308c7e64476c9899c59ea3e690aa6

Round two begins on the next post. OP will be updated.

[🏰 TradeFortress 🏰]

Why bother, seriously?

[Dabs]

Why bother, seriously?

I've got to start somewhere. You never know, maybe the next round picks up more players. And I just don't like the way the other raffles or lottos are working now. (Nothing against their provable fairness or anything, I just don't like them.)

Also, compared to the previous lotto operator, I'm not an unknown. I'm not saying I'm known, just that I'm not unknown.

[MPOE-PR]

I've got to start somewhere.

Pretty hard to argue with that one.

[Dabs]

Next game is here:
https://bitcointalk.org/index.php?topic=212855.0