A057712 - OEIS

A057712

Number of "polyhes" of order n: a polyhe of order n is obtained by taking a polyhex made of n hexagons (A000228); cutting each of the n hexagons along a diameter and throwing away half that hexagon, in such a way that the remaining figure (made of n half-hexagons) is connected.

1, 4, 13, 60, 276, 1416, 7201, 37972, 201989, 1089815, 5929666, 32533673, 179657435

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

REFERENCES

Enumeration of a(1)-a(8) attributed by Andrew Clarke to Brendan Owen.

LINKS

Table of n, a(n) for n=1..13.

Abaroth's World, Polyhes, Polyhalfhexes & Polytriamonds

Andrew Clarke, Polyhes

Andrew Clarke, Picture showing triangle formed by combining polyhes of orders 1, 2 and 3.

Eric Weisstein's World of Mathematics, Polyhe