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.

A346746 E.g.f.: exp( (x * exp(x) - sinh(x)) / 2 ).

Original entry on oeis.org

1, 0, 1, 1, 5, 12, 58, 220, 1145, 5684, 33284, 198412, 1306355, 8945046, 65658392, 503505600, 4076565489, 34442610648, 304577372128, 2802673411280, 26840614943667, 266644080930194, 2745669007978680, 29243006731749200, 321810005123384617, 3653558357684804324
Offset: 0

Views

Author

Ilya Gutkovskiy, Aug 01 2021

Keywords

Comments

Exponential transform of A004526.

Crossrefs

Programs

  • Mathematica
    nmax = 25; CoefficientList[Series[Exp[(x Exp[x] - Sinh[x])/2], {x, 0, nmax}], x] Range[0, nmax]!
    a[0] = 1; a[n_] := a[n] = Sum[Binomial[n - 1, k - 1] Floor[k/2] a[n - k], {k, 1, n}]; Table[a[n], {n, 0, 25}]

Formula

a(0) = 1; a(n) = Sum_{k=1..n} binomial(n-1,k-1) * A004526(k) * a(n-k).

A346748 E.g.f.: exp( (x * exp(-x) + sinh(x)) / 2 ).

Original entry on oeis.org

1, 1, 0, 0, 4, -1, -9, 103, -132, -535, 7731, -25117, -18072, 1078215, -6917039, 16312667, 186611792, -2454241183, 14370311311, 1436259867, -934228834216, 10658996229479, -54990712418263, -185381404760729, 7270919988375200, -80130195880201583, 391992372213719679
Offset: 0

Views

Author

Ilya Gutkovskiy, Aug 01 2021

Keywords

Comments

Exponential transform of A001057.

Crossrefs

Programs

  • Mathematica
    nmax = 26; CoefficientList[Series[Exp[(x Exp[-x] + Sinh[x])/2], {x, 0, nmax}], x] Range[0, nmax]!
    a[0] = 1; a[n_] := a[n] = Sum[(-1)^(k + 1) Binomial[n - 1, k - 1] Floor[(k + 1)/2] a[n - k], {k, 1, n}]; Table[a[n], {n, 0, 26}]

Formula

a(0) = 1; a(n) = Sum_{k=1..n} binomial(n-1,k-1) * A001057(k) * a(n-k).

Extensions

Typo in a(26) corrected by Georg Fischer, Nov 30 2021
Showing 1-2 of 2 results.