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.

Showing 1-3 of 3 results.

A365734 G.f. satisfies A(x) = 1 + x*A(x) / (1 - x^5*A(x)^2).

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 2, 5, 11, 21, 36, 58, 94, 163, 306, 599, 1170, 2229, 4140, 7596, 14002, 26228, 49979, 96212, 185491, 356255, 681247, 1300680, 2488500, 4782037, 9231306, 17875306, 34656389, 67194497, 130263382, 252631688, 490513867, 953923030, 1858136173, 3624102244
Offset: 0

Views

Author

Seiichi Manyama, Sep 17 2023

Keywords

Crossrefs

Programs

  • PARI
    a(n) = sum(k=0, n\5, binomial(n-4*k-1, k)*binomial(n-3*k+1, n-5*k)/(n-3*k+1));

Formula

a(n) = Sum_{k=0..floor(n/5)} binomial(n-4*k-1,k) * binomial(n-3*k+1,n-5*k) / (n-3*k+1).

A365735 G.f. satisfies A(x) = 1 + x*A(x) / (1 - x^5*A(x)^3).

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 2, 6, 16, 36, 71, 128, 223, 403, 796, 1706, 3775, 8252, 17485, 35986, 72988, 148594, 307833, 650947, 1395846, 3004732, 6443836, 13732127, 29134320, 61792707, 131525272, 281463507, 605273669, 1305373379, 2817407854, 6077804871, 13103021422
Offset: 0

Views

Author

Seiichi Manyama, Sep 17 2023

Keywords

Crossrefs

Programs

  • PARI
    a(n) = sum(k=0, n\5, binomial(n-4*k-1, k)*binomial(n-2*k+1, n-5*k)/(n-2*k+1));

Formula

a(n) = Sum_{k=0..floor(n/5)} binomial(n-4*k-1,k) * binomial(n-2*k+1,n-5*k) / (n-2*k+1).

A365798 G.f. satisfies A(x) = 1 + x*A(x)*(1 + x^5*A(x)^4).

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 2, 7, 22, 57, 127, 253, 468, 848, 1618, 3433, 8009, 19384, 46264, 106369, 235179, 505955, 1079790, 2332555, 5166405, 11737860, 27086236, 62676956, 144074416, 327837356, 739787486, 1663922487, 3751649542, 8513640107, 19464624667
Offset: 0

Views

Author

Seiichi Manyama, Sep 19 2023

Keywords

Crossrefs

Programs

  • PARI
    a(n) = sum(k=0, n\6, binomial(n-5*k, k)*binomial(n-k+1, n-5*k)/(n-k+1));

Formula

a(n) = Sum_{k=0..floor(n/6)} binomial(n-5*k,k) * binomial(n-k+1,n-5*k) / (n-k+1) = Sum_{k=0..floor(n/6)} binomial(n-k,5*k) * binomial(5*k,k) / (4*k+1).
Showing 1-3 of 3 results.