cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A174439 Partial sums of A001523.

Original entry on oeis.org

1, 2, 4, 8, 16, 31, 58, 105, 184, 314, 523, 853, 1365, 2149, 3332, 5097, 7701, 11505, 17009, 24907, 36147, 52027, 74304, 105352, 148355, 207575, 288673, 399157, 548926, 750996, 1022400, 1385374, 1868813, 2510181, 3357862, 4474187, 5939186
Offset: 0

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Author

Jonathan Vos Post, Mar 19 2010

Keywords

Comments

The subsequence of primes begins: 2, 31, 523, 853, 24907, 52027, 1868813, ...

Crossrefs

Programs

  • Mathematica
    nmax = 41; A001523 = CoefficientList[Series[1 + Sum[(-1)^(k + 1)*x^(k*(k + 1)/2), {k, 1, nmax}] / QPochhammer[x]^2, {x, 0, nmax}], x]; s = 0; Table[s = s + A001523[[k]], {k, 1, nmax}] (* Vaclav Kotesovec, Dec 13 2015 *)

Formula

a(n) = Sum_{i=0..n} A001523(i).
a(n) ~ exp(2*Pi*sqrt(n/3))/(8*Pi*3^(1/4)*n^(3/4)). - Vaclav Kotesovec, Dec 13 2015