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A142886 Number of polyominoes with n cells that have the symmetry group D_4. 17
1, 1, 0, 0, 1, 1, 0, 0, 1, 2, 0, 0, 3, 2, 0, 0, 5, 4, 0, 0, 12, 7, 0, 0, 20, 11, 0, 0, 45 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,10

COMMENTS

This is the largest possible symmetry group that a polyomino can have.

LINKS

Table of n, a(n) for n=0..28.

Tomás Oliveira e Silva, Enumeration of polyominoes

D. H. Redelmeier, Counting polyominoes: yet another attack, Discrete Math., 36 (1981), 191-203.

D. H. Redelmeier, Table 3 of Counting polyominoes...

Index entries for sequences related to groups

CROSSREFS

Sequences classifying polyominoes by symmetry group: A000105, A006746, A006747, A006748, A006749, A056877, A056878, A142886, A144553, A144554.

Sequence in context: A259827 A143161 A225853 * A099026 A205341 A195664

Adjacent sequences:  A142883 A142884 A142885 * A142887 A142888 A142889

KEYWORD

nonn,more,changed

AUTHOR

N. J. A. Sloane, Jan 01 2009

EXTENSIONS

Name corrected by Wesley Prosser, Sep 06 2017

a(28) added by Andrew Howroyd, Dec 04 2018

STATUS

approved

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Last modified December 12 19:33 EST 2018. Contains 318081 sequences. (Running on oeis4.)