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.

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A352529 Expansion of 1/Sum_{k>=0} x^(k^4).

Original entry on oeis.org

1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 0, 1, -2, 3, -4, 5, -6, 7, -8, 9, -10, 11, -12, 13, -14, 15, -15, 14, -12, 9, -5, 0, 6, -13, 21, -30, 40, -51, 63, -76, 90, -105, 120, -134, 146, -155, 160, -160, 154, -141, 120, -90, 50, 1, -64, 140, -230, 335, -455, 589, -735, 890, -1050, 1210, -1364, 1505
Offset: 0

Views

Author

Seiichi Manyama, Mar 19 2022

Keywords

Crossrefs

Programs

  • PARI
    my(N=99, x='x+O('x^N)); Vec(1/sum(k=0, N^(1/4), x^k^4))
    
  • PARI
    a(n) = if(n==0, 1, -sum(k=1, n, ispower(k, 4)*a(n-k)));

A363749 Number of compositions into sums of fifth powers.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 35, 38, 42, 47, 53, 60, 68, 77, 87, 98, 110, 123, 137, 152, 168, 185
Offset: 0

Views

Author

Seiichi Manyama, Jun 19 2023

Keywords

Comments

This sequence is different from A291168.

Crossrefs

Programs

  • PARI
    a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=sum(j=1, i, ispower(j, 5)*v[i-j+1])); v;

Formula

G.f.: 1/(1 - Sum_{k>=1} x^(k^5)).
Showing 1-2 of 2 results.