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 1-4 of 4 results.

A368440 Expansion of e.g.f. exp(x) / (3 - 2*exp(3*x)).

Original entry on oeis.org

1, 7, 103, 2287, 67687, 2504047, 111163303, 5757411247, 340788559207, 22693176094447, 1679047763217703, 136654363293340207, 12133120656211741927, 1167034341869994747247, 120886955198779063694503, 13416476227330202250197167, 1588276885073067052758303847
Offset: 0

Views

Author

Seiichi Manyama, Dec 24 2023

Keywords

Crossrefs

Programs

  • PARI
    a_vector(n) = my(v=vector(n+1)); for(i=0, n, v[i+1]=1+2*sum(j=1, i, 3^j*binomial(i, j)*v[i-j+1])); v;

Formula

a(n) = 1 + 2 * Sum_{k=1..n} 3^k * binomial(n,k) * a(n-k).

A368441 Expansion of e.g.f. exp(x) / (4 - 3*exp(3*x)).

Original entry on oeis.org

1, 10, 208, 6508, 271468, 14154580, 885638908, 64649204308, 5393387534428, 506188870889140, 52786278954586108, 6055112126576175508, 757725480419984012188, 102722055234542078115700, 14996854976334688765608508, 2345848207305916218955201108
Offset: 0

Views

Author

Seiichi Manyama, Dec 24 2023

Keywords

Crossrefs

Programs

  • PARI
    a_vector(n) = my(v=vector(n+1)); for(i=0, n, v[i+1]=1+3*sum(j=1, i, 3^j*binomial(i, j)*v[i-j+1])); v;

Formula

a(n) = 1 + 3 * Sum_{k=1..n} 3^k * binomial(n,k) * a(n-k).

A368450 Expansion of e.g.f. exp(x) / (1 + log(1 - 3*x)/3).

Original entry on oeis.org

1, 2, 8, 61, 695, 10310, 187024, 4002131, 98593949, 2746565218, 85333213856, 2924626915529, 109588276298995, 4456269669580742, 195418762093000328, 9192090435429906463, 461630086359185798777, 24651183861530752336994, 1394716088179233110318104
Offset: 0

Views

Author

Seiichi Manyama, Dec 24 2023

Keywords

Crossrefs

Programs

  • PARI
    a_vector(n) = my(v=vector(n+1)); for(i=0, n, v[i+1]=1+sum(j=1, i, 3^(j-1)*(j-1)!*binomial(i, j)*v[i-j+1])); v;

Formula

a(n) = 1 + Sum_{k=1..n} 3^(k-1) * (k-1)! * binomial(n,k) * a(n-k).

A368455 Expansion of e.g.f. 3*exp(-x) / (4 - exp(3*x)).

Original entry on oeis.org

1, 0, 4, 20, 180, 1940, 25204, 381780, 6609460, 128728340, 2785737204, 66312995540, 1722049711540, 48445655125140, 1467738434962804, 47643726641609300, 1649648835729498420, 60688474959603256340, 2363983970307953910004, 97199476595104080495060
Offset: 0

Views

Author

Seiichi Manyama, Dec 24 2023

Keywords

Crossrefs

Programs

  • PARI
    a_vector(n) = my(v=vector(n+1)); for(i=0, n, v[i+1]=(-1)^i+sum(j=1, i, 3^(j-1)*binomial(i, j)*v[i-j+1])); v;

Formula

a(n) = (-1)^n + Sum_{k=1..n} 3^(k-1) * binomial(n,k) * a(n-k).
Showing 1-4 of 4 results.