Heptiamond Compatibility

Introduction

A heptiamond is a figure made of seven equilateral triangles joined edge to edge. There are 24 such figures, not distinguishing reflections and rotations.

Dr. Erich Friedman's Math Magic for September 2004 shows compatibility figures for polyiamonds up to order 6 (and many other polyforms). Here I present the smallest known compatibility figures for heptiamonds.

Summary

I adopt the nomenclature of K. Ishino's Heptiamonds Page.

 ABCDEFGHIJKLMNPQRSTUVXYZ
A*233232310323633322363663
B2*362322262223183322——633
C33*3323322?2624323222423
D363*333622?3633323633663
E2233*2322623663332333322
F33232*26323363262623??23
G223332*222622222232?31224
H3236262*262326223232?262
I102222322*2?2929922444?22
J362262262*36?32224322?22
K22??2362?3*363636233—336
L32233323263*22?2332312?64
M626666229?62*2?212186???62
N3323632623322*33333?2?62
P318433222926??3*362633222
Q333336229232233*2234?1862
R23223223226312362*2233626
S223326322423183222*346222
T322632234332636323*618623
U6—2333?24233??34346*2366
V3—233?3?42—12?23?36182*663
X66463?122??3???21862636*32
Y6326222622366626222663*2
Z33332342226422226236322*

Figures

First the pairs:

Then those with 3 or 4 tiles:

Then the big ones, with at least 6 tiles:

Back to Polyform Curiosities.
Col. G. L. Sicherman [ HOME | MAIL ]