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A309159 Number of generalized polyforms on the snub square tiling with n cells. 0
1, 2, 2, 4, 10, 28, 79, 235, 720, 2254, 7146, 22927, 74137, 241461, 790838, 2603210, 8604861, 28549166, 95027832, 317229779, 1061764660, 3562113987, 11976146355 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

The generalized polyforms counted by this sequence are "free", which means that they are counted up to rotation and reflection.

LINKS

Table of n, a(n) for n=0..22.

Peter Kagey, Counting generalized polyominoes

Wikipedia, Snub square tiling

CROSSREFS

Cf. A000105, A000228, A000577.

Sequence in context: A132824 A298898 A078801 * A002420 A284016 A112556

Adjacent sequences:  A309156 A309157 A309158 * A309160 A309161 A309162

KEYWORD

nonn

AUTHOR

Peter Kagey and Peter Taylor, Jul 15 2019

EXTENSIONS

a(19)-a(22) from Christian Sievers

STATUS

approved

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Last modified December 8 02:30 EST 2019. Contains 329850 sequences. (Running on oeis4.)