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.

A383799 Irregular triangle: T(n,k) gives the number of k-polysticks on edges of the n-cube up to rotational symmetries of the n-cube, with 0 <= k <= A001787(n).

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 4, 6, 14, 24, 32, 25, 13, 5, 1, 1, 1, 1, 1, 4, 10, 35, 131, 510, 1932, 7123, 24466, 76829, 214685, 518820, 1050433, 1727591, 2273998, 2446653, 2212119, 1709579, 1143416, 663450, 335186, 146371, 55327, 17767, 4898, 1103, 226, 35, 7, 1, 1
Offset: 1

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Author

Peter Kagey, May 10 2025

Keywords

Comments

Row 3 gives the number of polyforms with n cells on the faces of a rhombic dodecahedron up to rotation.

Examples

			Table begins:
n\k| 0  1  2  3   4   5    6    7     8     9     10     11      12
---+----------------------------------------------------------------
  1| 1, 1;
  2| 1, 1, 1, 1,  1;
  3| 1, 1, 1, 4,  6, 14,  24,  32,   25,   13,     5,     1,      1;
  4| 1, 1, 1, 4, 10, 35, 131, 510, 1932, 7123, 24466, 76829, 214685, ...
		

Crossrefs

Cf. A333333 (analogous with reflectional symmetries allowed).

Formula

A222186(n) = Sum_{k=0..n*2^(n-1)} T(n,k) - Sum_{k=0..(n-1)*2^(n-2)} T(n-1,k) for n >= 2. - Pontus von Brömssen, May 12 2025

Extensions

a(30)-a(40) from Pontus von Brömssen, May 14 2025
a(41)-a(53) from Pontus von Brömssen, Jun 11 2025