# Tetraming Oddities

A *tetraming* is a plane figure formed by joining four
cells in the equilateral triangular grid along edges or at corners or both.
There are 75 tetramings, independent of reflection.
An *oddity*
is a figure with binary symmetry formed by an odd number of copies of
a polyform.
Here are the minimal known tetraming oddities with various symmetries.
Please write if you find a smaller solution or solve an unsolved case.

## Horizontal Mirror Symmetry

## Vertical Mirror Symmetry

## 2-Rotary Symmetry On Vertex

## 2-Rotary Symmetry On Edge

## Horizontal and Vertical Symmetry On Vertex

## Horizontal and Vertical Symmetry On Edge

## 6-Rotary Symmetry

## Full Symmetry

*Last revised 2021-01-03.*

Back to Polyform Oddities
<
Polyform Curiosities

Col. George Sicherman
[ HOME
| MAIL
]