Is a vanity address hard to make?
Around 58x harder for each letter you want fix. So yes, they start to become hard pretty quickly.
58 valid character for the other spots
27 characters: (21)^58 (4*10^27) possible
28 characters: (22)^58(7*10^77) possible
Do I have my math confused? (It's been known to happen from time to time).
Shouldn't it be 58
21 and 58
22 (not 21
58 and 22
58)?
Then again, you do have a PRIMEDICE ad in your sig, and I've generally found that 99% of the people who have such signatures don't have any idea what they are talking about and are just spouting nonsense to get their post count up so they can collect more for the advertisement.
I'll just click "ignore" on your ID until I see some reason to do otherwise.
Its too easy point others errors when you just throw numbers from the thin air, giving no clue where they came from, so no one has a chance to verify if they are correct or at least make any sense at all. Keep your good job, mister "I ignore others because I'm superior and the signature program dudes are a bunch of dumb people"