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A024502
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a(n) = floor(C(2n,n)/2^n).
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1
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1, 1, 1, 2, 4, 7, 14, 26, 50, 94, 180, 344, 660, 1269, 2448, 4733, 9171, 17804, 34618, 67415, 131460, 256661, 501656, 981501, 1922106, 3767329, 7389761, 14505829, 28493592, 56004648, 110142474, 216731966, 426691058, 840452084, 1656184990
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OFFSET
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0,4
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LINKS
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FORMULA
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EXAMPLE
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a(4) = floor(1*3*5*7 / (1*2*3*4)) = floor(35/8) = 4.
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MATHEMATICA
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Table[Floor[Binomial[2n, n]/2^n], {n, 0, 40}] (* Harvey P. Dale, Mar 07 2016 *)
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PROG
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(Python)
import math
for n in range(55): print(str(math.factorial(2*n)//(math.factorial(n)**2 * 2**n)), end=', ')
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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