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.

A014329 Convolution of partition numbers and Catalan numbers.

Original entry on oeis.org

1, 2, 5, 12, 31, 84, 245, 752, 2413, 7991, 27104, 93605, 327886, 1161735, 4155323, 14982399, 54393829, 198666117, 729443563, 2690890444, 9968312790, 37066929338, 138304185107, 517646986719, 1942966098461, 7311862919106, 27582428518833, 104279585166245
Offset: 0

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Author

Keywords

Crossrefs

Programs

Formula

a(n) ~ c * 4^n / (sqrt(Pi) * n^(3/2)), where c = Sum_{k>=0} A000041(k)/4^k = 1/QPochhammer[1/4, 1/4] = 1.4523536424495970158347130224852748733612279788... . - Vaclav Kotesovec, Jun 23 2015
G.f.: (1 - sqrt(1-4*x))/(2*x*QPochhammer(x)). - G. C. Greubel, Jan 08 2023

A304823 Convolution of number of partitions into distinct parts and central binomial coefficients.

Original entry on oeis.org

1, 3, 9, 30, 102, 361, 1308, 4819, 17970, 67614, 256156, 975742, 3733255, 14336290, 55224880, 213298817, 825741010, 3203142338, 12447523904, 48448301960, 188838707898, 736985826174, 2879588370517, 11263139964066, 44096779183060, 172797721166402
Offset: 0

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Author

Vaclav Kotesovec, May 19 2018

Keywords

Crossrefs

Programs

  • Mathematica
    Table[Sum[PartitionsQ[n-k]*Binomial[2*k, k], {k, 0, n}], {n, 0, 25}]

Formula

a(n) ~ QPochhammer[-1, 1/4] * 2^(2*n-1) / sqrt(Pi*n).

A292619 Convolution of number of overpartitions and Catalan numbers.

Original entry on oeis.org

1, 3, 8, 21, 54, 144, 404, 1195, 3712, 12000, 39994, 136400, 473430, 1665868, 5926476, 21275805, 76964808, 280250088, 1026309908, 3777411342, 13965286180, 51837285776, 193107846304, 721732334136, 2705480787422, 10169387310362, 38320472420462, 144733083435688
Offset: 0

Views

Author

Vaclav Kotesovec, Sep 20 2017

Keywords

Crossrefs

Programs

  • Mathematica
    Table[Sum[Sum[PartitionsP[k-j] * PartitionsQ[j], {j, 0, k}] * CatalanNumber[n-k], {k, 0, n}], {n, 0, 50}]

Formula

a(n) ~ c * 4^n / (sqrt(Pi) * n^(3/2)), where c = QPochhammer[-1, 1/4] / (2*QPochhammer[1/4, 1/4]) = 1.96926035366826943194719369696726567...
Showing 1-3 of 3 results.