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.

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A338956 Number of oriented colorings of the 96 edges (or triangular faces) of the 4-D 24-cell using exactly n colors.

Original entry on oeis.org

1, 137548893254081168086800766, 11046328890861010626464488614428032600986342, 10897746068335468788318134977474134922662053604436974448, 21912802868317153141871319582922663027477920477404414535105616050
Offset: 1

Views

Author

Robert A. Russell, Nov 17 2020

Keywords

Comments

Each chiral pair is counted as two when enumerating oriented arrangements. The Schläfli symbol of the 24-cell is {3,4,3}. It has 24 octahedral facets. It is self-dual. For n>96, a(n) = 0.

Crossrefs

Cf. A338957 (unoriented), A338958 (chiral), A338959 (achiral), A338952 (up to n colors), A338948 (vertices, facets), A331350 (5-cell), A331358 (8-cell edges, 16-cell faces), A331354 (16-cell edges, 8-cell faces), A338980 (120-cell, 600-cell).

Programs

  • Mathematica
    bp[j_] := Sum[k! StirlingS2[j, k] x^k, {k, 0, j}] (* binomial series *)
    Drop[CoefficientList[bp[8]/6+bp[12]/4+bp[16]/12+bp[18]/18+7bp[24]/48+bp[32]/12+bp[36]/18+19bp[48]/576+bp[50]/8+bp[96]/576,x],1]

Formula

A338952(n) = Sum_{j=1..Min(n,96)} a(n) * binomial(n,j).
a(n) = A338957(n) + A338958(n) = 2*A338957(n) - A338959(n) = 2*A338958(n) + A338959(n).
Previous Showing 11-11 of 11 results.