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A256277
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C(2*n,n) mod 2*n+1.
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1
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2, 1, 6, 7, 10, 1, 12, 1, 18, 19, 22, 6, 11, 1, 30, 9, 15, 1, 15, 1, 42, 15, 46, 29, 36, 1, 27, 55, 58, 1, 14, 19, 66, 21, 70, 1, 32, 35, 78, 43, 82, 40, 60, 1, 7, 60, 70, 1, 18, 1, 102, 96, 106, 1, 39, 1, 17, 96, 3, 111, 84, 31, 126, 84, 130, 37, 30, 1
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OFFSET
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1,1
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COMMENTS
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a(n) == (-1)^n (mod 2*n+1) if 2*n+1 is prime or is in A163209.
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LINKS
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MAPLE
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seq(binomial(2*n, n) mod (2*n+1), n=1..100); # Robert Israel, Jun 12 2015
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MATHEMATICA
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PROG
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(Magma) [Binomial(2*n, n) mod (2*n+1): n in [1..70]]; // Vincenzo Librandi, May 03 2016
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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