Polyhex

In recreational mathematics, a polyhex is a polyform with a regular hexagon (or 'hex' for short) as the base form.

The number of polyhexes made from a given number of hexagons:

1. 1

2. 1

3. 3

4. 7

5. 22

6. 81

7. 331

8. 1,435

9. 6,505

10. 30,086

11. 141,229

12. 669,584

13. 3,198,256

Source: Vöge, Markus; Guttmann, Anthony J.; Jensen, Iwan. “On the number of benzenoid hydrocarbons.” J. Chem. Inf. Comput. Sci. 42, 456-66 (2002).