# 108 Heptominoes

From ProofWiki

## Theorem

There exist $108$ distinct heptominoes, up to reflection, one of which has a hole:

## Proof

## Sources

- 1997: David Wells:
*Curious and Interesting Numbers*(2nd ed.) ... (previous) ... (next): $35$ - 1997: David Wells:
*Curious and Interesting Numbers*(2nd ed.) ... (previous) ... (next): $108$

- Weisstein, Eric W. "Heptomino." From
*MathWorld*--A Wolfram Web Resource. http://mathworld.wolfram.com/Heptomino.html