I had no idea of the specific date when Bitcoin began so I approximated from today's block #.
Is this table correct ? If so, could we add It to the wiki ?
No. It's not correct, you've used floating point and suffered from numerical precision problems you also started at the wrong point, as you noted. The first block is trivially found, its coded into every copy of bitcoin.
http://blockexplorer.com/b/0Assuming the precision of bitcoin is not increased:
python one liner
print "".join(["%0.8f %d %0.8f\n"%(5000000000/2**x/float(1e8),(x+1)*210000,sum([5000000000/2**y*210000 for y in range(x+1)])/float(1e8)) for x in range(34)])
50.00000000 0210000 10500000.00000000
25.00000000 0420000 15750000.00000000
12.50000000 0630000 18375000.00000000
06.25000000 0840000 19687500.00000000
03.12500000 1050000 20343750.00000000
01.56250000 1260000 20671875.00000000
00.78125000 1470000 20835937.50000000
00.39062500 1680000 20917968.75000000
00.19531250 1890000 20958984.37500000
00.09765625 2100000 20979492.18750000
00.04882812 2310000 20989746.09270000
00.02441406 2520000 20994873.04530000
00.01220703 2730000 20997436.52160000
00.00610351 2940000 20998718.25870000
00.00305175 3150000 20999359.12620000
00.00152587 3360000 20999679.55890000
00.00076293 3570000 20999839.77420000
00.00038146 3780000 20999919.88080000
00.00019073 3990000 20999959.93410000
00.00009536 4200000 20999979.95970000
00.00004768 4410000 20999989.97250000
00.00002384 4620000 20999994.97890000
00.00001192 4830000 20999997.48210000
00.00000596 5040000 20999998.73370000
00.00000298 5250000 20999999.35950000
00.00000149 5460000 20999999.67240000
00.00000074 5670000 20999999.82780000
00.00000037 5880000 20999999.90550000
00.00000018 6090000 20999999.94330000
00.00000009 6300000 20999999.96220000
00.00000004 6510000 20999999.97060000
00.00000002 6720000 20999999.97480000
00.00000001 6930000 20999999.97690000
00.00000000 7140000 20999999.97690000
(make up your own dates, — any dates are going to be somewhat approximate)