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.

A087154 Number of partitions of n into distinct nonsquares.

Original entry on oeis.org

1, 0, 1, 1, 0, 2, 1, 2, 3, 2, 4, 4, 4, 7, 6, 9, 9, 11, 14, 14, 19, 21, 23, 29, 31, 36, 43, 46, 56, 62, 70, 81, 91, 103, 117, 132, 148, 167, 188, 211, 237, 266, 297, 332, 371, 414, 461, 515, 571, 634, 708, 780, 870, 963, 1062, 1180, 1300, 1436, 1588, 1747, 1929, 2123
Offset: 0

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Author

Reinhard Zumkeller, Aug 21 2003

Keywords

Examples

			n=7: 2+5 = 7: a(7)=2;
n=8: 2+6 = 3+5 = 8: a(8)=3;
n=9: 2+7 = 3+6: a(9)=2.
		

Crossrefs

Programs

  • Haskell
    a087154 = p a000037_list where
       p _      0 = 1
       p (k:ks) m = if m < k then 0 else p ks (m - k) + p ks m
    -- Reinhard Zumkeller, Apr 25 2013
  • Mathematica
    nmax = 100; CoefficientList[Series[Product[(1 + x^k)/(1 + x^(k^2)), {k, 1, nmax}], {x, 0, nmax}], x] (* Vaclav Kotesovec, Dec 29 2016 *)

Formula

G.f.: Product_{m>0} (1+x^m)/(1+x^(m^2)). - Vladeta Jovovic, Jul 31 2004
a(n) ~ exp(Pi*sqrt(n/3) - 3^(1/4) * (sqrt(2)-1) * Zeta(3/2) * n^(1/4) / 2 - 3*(sqrt(2)-1)^2 * Zeta(3/2)^2 / (32*Pi)) / (2^(3/2) * 3^(1/4) * n^(3/4)). - Vaclav Kotesovec, Dec 30 2016

Extensions

Zeroth term added by Franklin T. Adams-Watters, Jan 25 2010