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A057420 Axially symmetric n-celled polyominoes with 1 hole. 0
1, 3, 8, 25, 45, 137, 221, 650, 1006, 2857, 4370, 12050, 18417, 49516, 76037, 200184, 309411, 800440, 1245934, 3176482 (list; graph; refs; listen; history; internal format)
OFFSET

9,2

LINKS

Tomas Oliveira e Silva, Enumeration of polyominoes

CROSSREFS

Sequence in context: A102919 A102476 A180380 * A076049 A026970 A026980

Adjacent sequences:  A057417 A057418 A057419 * A057421 A057422 A057423

KEYWORD

nonn

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Sep 05 2000

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Last modified February 16 06:27 EST 2012. Contains 205860 sequences.