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 1-2 of 2 results.

A371005 Expansion of e.g.f. (1/x) * Series_Reversion( x/(2*exp(x) - 1) ).

Original entry on oeis.org

1, 2, 10, 86, 1074, 17742, 366026, 9074102, 263006050, 8732015390, 326876957562, 13624410416454, 625859432308754, 31418430350730542, 1711378030988087338, 100535991279811936982, 6336275006902469756610, 426480351471985076800062
Offset: 0

Views

Author

Seiichi Manyama, Mar 08 2024

Keywords

Crossrefs

Programs

  • PARI
    my(N=20, x='x+O('x^N)); Vec(serlaplace(serreverse(x/(2*exp(x)-1))/x))
    
  • PARI
    a(n) = sum(k=0, n+1, 2^k*(-1)^(n+1-k)*k^n*binomial(n+1, k))/(n+1);

Formula

a(n) = 1/(n+1) * Sum_{k=0..n+1} 2^k * (-1)^(n+1-k) * k^n * binomial(n+1,k).
a(n) = n! * Sum_{k=0..n} 2^k * Stirling2(n,k)/(n-k+1)!. - Seiichi Manyama, Nov 07 2024

A377790 Expansion of e.g.f. (1/x) * Series_Reversion( x/(1 - 3*log(1-x)) ).

Original entry on oeis.org

1, 3, 21, 249, 4302, 98982, 2860686, 99779418, 4081683744, 191696903424, 10168315038360, 601321398385320, 39230551252853424, 2799199551778309872, 216856533870111053520, 18127987493141612555280, 1626479163148212406506240, 155902932291162161594016000
Offset: 0

Views

Author

Seiichi Manyama, Nov 07 2024

Keywords

Crossrefs

Programs

  • PARI
    my(N=20, x='x+O('x^N)); Vec(serlaplace(serreverse(x/(1-3*log(1-x)))/x))
    
  • PARI
    a(n) = n!*sum(k=0, n, 3^k*abs(stirling(n, k, 1))/(n-k+1)!);

Formula

a(n) = n! * Sum_{k=0..n} 3^k * |Stirling1(n,k)|/(n-k+1)!.
Showing 1-2 of 2 results.