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.

A307321 Expansion of Product_{j>=1} 1/(1 - (-1 + Product_{k>=1} 1/(1 - x^k)^k)^j)^j.

Original entry on oeis.org

1, 1, 6, 30, 143, 660, 3000, 13448, 59696, 262788, 1148738, 4989908, 21551733, 92596511, 395921737, 1685304092, 7143861196, 30163965903, 126895681419, 531986033218, 2222961809367, 9260148591001, 38461580964389, 159302487751844, 658054630483936, 2711429650817356
Offset: 0

Views

Author

Ilya Gutkovskiy, Apr 02 2019

Keywords

Crossrefs

Programs

  • Mathematica
    nmax = 25; CoefficientList[Series[Product[1/(1 - (-1 + Product[1/(1 - x^k)^k, {k, 1, nmax}])^j)^j, {j, 1, nmax}], {x, 0, nmax}], x]

Formula

G.f.: g(g(x) - 1), where g(x) = g.f. of A000219 (number of planar partitions).

A307566 Expansion of Product_{j>=1} (1 + j*(-1 + Product_{k>=1} (1 + k*x^k))^j).

Original entry on oeis.org

1, 1, 4, 18, 72, 289, 1119, 4301, 16408, 62313, 234914, 879822, 3274623, 12125348, 44707778, 164258803, 601535222, 2195926654, 7990792367, 28985219498, 104811279467, 377875493610, 1358584361039, 4872111113570, 17431266435024, 62229179950735, 221699783190996, 788274748711694
Offset: 0

Views

Author

Ilya Gutkovskiy, Apr 15 2019

Keywords

Crossrefs

Programs

  • Mathematica
    nmax = 27; CoefficientList[Series[Product[(1 + j (-1 + Product[(1 + k x^k), {k, 1, nmax}])^j), {j, 1, nmax}], {x, 0, nmax}], x]

Formula

G.f.: g(g(x) - 1), where g(x) = g.f. of A022629.

A307571 Expansion of Product_{j>=1} (1 + x^j*Product_{k>=1} (1 + x^k)^(k*j))^j.

Original entry on oeis.org

1, 1, 3, 11, 38, 129, 436, 1445, 4764, 15583, 50667, 163890, 527620, 1691368, 5400754, 17183173, 54487190, 172235992, 542844404, 1706169816, 5348478123, 16724698483, 52174714116, 162399459964, 504402061533, 1563430065203, 4836462927829, 14933470162894, 46026742326000, 141614337715832
Offset: 0

Views

Author

Ilya Gutkovskiy, Apr 15 2019

Keywords

Crossrefs

Programs

  • Mathematica
    nmax = 29; CoefficientList[Series[Product[(1 + x^j Product[(1 + x^k)^(k j), {k, 1, nmax}])^j, {j, 1, nmax}], {x, 0, nmax}], x]

Formula

G.f.: g(x*g(x)), where g(x) = g.f. of A026007.
Showing 1-3 of 3 results.