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A065350
a(n) = binomial(2*n, n) mod (n+1)^2.
4
2, 6, 4, 20, 0, 42, 40, 72, 20, 110, 120, 156, 56, 0, 208, 272, 108, 342, 200, 378, 176, 506, 432, 600, 260, 459, 0, 812, 840, 930, 928, 396, 476, 490, 360, 1332, 608, 1131, 1200, 1640, 0, 1806, 880, 0, 920, 2162, 864, 2352, 1100, 1224, 208, 2756, 1296, 2145
OFFSET
1,1
COMMENTS
a(A002503(n)) = 0. - Reinhard Zumkeller, Sep 16 2014
LINKS
MATHEMATICA
Table[Mod[Binomial[2 n, n], (n + 1)^2], {n, 100}] (* Bruno Berselli, Jan 06 2014 *)
PROG
(PARI) a(n) = { binomial(2*n, n) % (n + 1)^2 } \\ Harry J. Smith, Oct 17 2009
(Haskell)
a065350 n = a065350_list !! (n-1)
a065350_list = zipWith mod (tail a000984_list) (drop 2 a000290_list)
-- Reinhard Zumkeller, Sep 16 2014
CROSSREFS
KEYWORD
nonn,changed
AUTHOR
Labos Elemer, Oct 30 2001
STATUS
approved