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A057426 Number of asymmetric n-celled polyominoes with 1 hole. 0
0, 0, 0, 0, 0, 0, 0, 5, 31, 185, 947, 4564, 21004, 93833, 410295, 1765378, 7504024, 31591157, 131982937, 547971412, 2263443059, 9309302775, 38149945673, 155858903955, 635066943350, 2581736396181 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,8

LINKS

Table of n, a(n) for n=1..26.

Tomás Oliveira e Silva, Enumeration of polyominoes

CROSSREFS

Sequence in context: A078526 A255236 A202753 * A329014 A015540 A014987

Adjacent sequences:  A057423 A057424 A057425 * A057427 A057428 A057429

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Sep 05 2000

STATUS

approved

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Last modified December 15 04:23 EST 2019. Contains 329991 sequences. (Running on oeis4.)