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Search: id:A051257
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| A051257 |
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Numbers formed from binomial coefficients (mod 2+k) interpreted as digits in factorial base. |
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+0
1
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| 1, 3, 11, 43, 231, 1337, 9739, 76209, 706109, 6914977, 78150249, 920172983, 12216376453, 168531536319, 2571960399839, 40581616143967, 701349512411763, 12460393480873445, 240094506439569631, 4749510978132662277
(list; graph; listen)
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OFFSET
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0,2
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FORMULA
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a(n) = Sum (k+1)!(C(n, k) mod (2+k)), k=0..n
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EXAMPLE
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a(5) = (1 mod 2)1!+(5 mod 3)2!+(10 mod 4)3!+(10 mod 5)4!+(5 mod 6)5!+(1 mod 7)6! = 1*1+2*2+2*6+0*24+5*120+1*720 = 1337
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MAPLE
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a(n) := proc(n) local i; RETURN(add(((binomial(n, i)mod(i+2))*((i+1)!)), i=0..n)); end;
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CROSSREFS
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Cf. A001317, A001339, A048757, A047999, A051256.
Sequence in context: A110052 A126282 A039627 this_sequence A135482 A126614 A000979
Adjacent sequences: A051254 A051255 A051256 this_sequence A051258 A051259 A051260
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KEYWORD
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nonn,nice
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AUTHOR
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Antti Karttunen Oct 24 1999
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