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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A371062 Number of one-sided generalized polyforms on the tetrahedral-octahedral honeycomb with n cells.

Original entry on oeis.org

1, 2, 1, 4, 11, 65, 339, 2211, 14356, 97599, 671518, 4696575, 33186688, 236773833, 1702530274, 12327097246, 89791558276
Offset: 0

Views

Author

Peter Kagey, Mar 09 2024

Keywords

Comments

This sequence counts "one-sided" polyforms where holes are allowed. This means that two polyforms are considered the same if one is a rotation of the other. However, reflections of chiral polytopes are considered distinct.
The ratio a(n)/A343909(n) -> 2 as n -> infinity.

Crossrefs

Extensions

a(10)-a(16) from Bert Dobbelaere, Jun 10 2025

A385028 Number of face-connected components of polyhedral cells in the bisymmetric hendecahedral honeycomb up to translation, rotation, and reflection of the honeycomb.

Original entry on oeis.org

1, 1, 4, 16, 116, 903, 8551
Offset: 0

Views

Author

Peter Kagey, Aug 13 2025

Keywords

Comments

These are "free polyforms" because they are counted up to rotation and reflection.
A bisymmetric hendecahedron is an 11-sided polyhedron that is similar to the convex hull of (-2,1,-1), (-2,1,1), (-1,-1,0), (0,-1,-1), (0,-1,1), (0,0,-2), (0,0,2), (0,2,0), (1,-1,0), (2,1,-1), and (2,1,1).

Examples

			For n = 2, the a(2) = 4 distinct compounds of two bisymmetric hendecahedra correspond to placing the four distinct types of faces (square, kite, rhombus, and triangle) together.
		

Crossrefs

Cf. A038119 (cubic), A038173 (rhombic dodecahedral), A038181 (truncated octahedral), A343909 (tetrahedral-octahedral), A365654 (square bipyramidal), A384254 (rectified cubic), A384274 (quarter cubic), A384754 (omnitruncated cubic), A385024 (tetragonal disphenoidal), A385025 (gyrobifastigium), A385026 (hexagonal prismatic), A385027 (triakis truncated tetrahedral), A385267 (half pyramidille), A385268 (oblate cubille), A385269 (quarter cubille), A385270 (elongated dodecahedral), A385271 (hexakis cubic), A385272 (phyllic disphenoidal), A385273 (quarter oblate octahedrille), A385274 (rhombic pyramidal), A385275 (square quarter pyramidille), A385276 (trapezo-rhombic dodecahedral), A385277 (triangular prismatic), A385278 (triangular pyramidille).
Previous Showing 21-22 of 22 results.