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A121943 Numbers n such that central binomial coefficient C(2n,n) is divisible by n^2. 0
1, 924, 1287, 2002, 2145, 3366, 3640, 3740, 4199, 6006, 6118, 6552, 7480, 7920, 8580, 8855, 10465, 10920, 11385, 11592, 12285, 12325, 12441, 12540, 12597, 12920, 13224, 13398, 13566, 15080, 15834, 18270, 18354, 18837, 18972, 19227 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

MATHEMATICA

Select[Table[n, {n, 20000}], IntegerQ[Binomial[2#, # ]/#^2] &]

CROSSREFS

Subsequence of A000984 = Central binomial coefficients: C(2n, n) = (2n)!/(n!)^2.

Sequence in context: A051984 A177810 A119396 * A024750 A024758 A172224

Adjacent sequences:  A121940 A121941 A121942 * A121944 A121945 A121946

KEYWORD

nonn

AUTHOR

Tanya Khovanova (tanyakh(AT)yahoo.com), Sep 03 2006

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Last modified February 13 09:48 EST 2012. Contains 205451 sequences.