A083560 Nearest integer to 1/sum(k>n,1/k^5).

1, 27, 176, 640, 1707, 3760, 7280, 12842, 21120, 32880, 48986, 70400, 98176, 133466, 177520, 231680, 297386, 376176, 469680, 579626, 707840, 856240, 1026842, 1221760, 1443200, 1693466, 1974960, 2290176, 2641706, 3032240, 3464560

Offset

1,2

Links

Table of n, a(n) for n=1..31.

Formula

n>2 a(n)=floor(4*n^4-8*n^3+28/3*n^2-16/3*n)

Empirical G.f.: x*(x^11-4*x^10+6*x^9-4*x^8+2*x^7-4*x^6-21*x^5-73*x^4-93*x^3-74*x^2-23*x-1) / ((x-1)^5*(x^2+x+1)). [Colin Barker, Dec 01 2012]

Prog

(PARI) a(n)=round(1/(zeta(5)-sum(k=1, n-1, 1/k^5)))

Crossrefs

Cf. A001844.

Sequence in context: A055339 A269054 A248234 * A125337 A126495 A224454

Adjacent sequences: A083557 A083558 A083559 * A083561 A083562 A083563

Keyword

nonn

Author

Benoit Cloitre, Jun 12 2003

Status

approved