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A024504
a(n) = floor(C(2n,n)/2^(n+1)).
0
0, 0, 0, 1, 2, 3, 7, 13, 25, 47, 90, 172, 330, 634, 1224, 2366, 4585, 8902, 17309, 33707, 65730, 128330, 250828, 490750, 961053, 1883664, 3694880, 7252914, 14246796, 28002324, 55071237, 108365983, 213345529, 420226042, 828092495, 1632525204
OFFSET
0,5
MATHEMATICA
Table[ Floor[ Binomial[2n, n]/2^(n + 1)], {n, 0, 35}] (* Robert G. Wilson v, Nov 26 2004 *)
CROSSREFS
Sequence in context: A213967 A128695 A378943 * A256494 A344432 A088172
KEYWORD
nonn
EXTENSIONS
More terms from Robert G. Wilson v, Nov 26 2004
STATUS
approved