Heptiamond Tri-Oddities

A polyiamond tri-oddity is a figure with ternary symmetry formed by some number of copies of a polyiamond that is not a multiple of three. Torsten Sillke first studied them in 1996.

Here are the minimal known tri-oddities for heptiamonds (7-iamonds). Unsolved heptiamonds are shown in grey. Please write if you find a smaller solution or solve an unsolved case.

For polyiamonds with fewer than 7 cells, see Polyiamond Tri-Oddities. For polyhexes, see Polyhex Tri-Oddities.

Arbitrary Solutions

Holeless Variants

Mirror Symmetry

These solutions have horizontal mirror symmetry as well as ternary symmetry.

Last revised 2017-09-02.


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Col. George Sicherman [ HOME | MAIL ]