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A089454 Number of n-celled polyominoes with exactly 2 holes. 4
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 41, 346, 2384, 14560, 81863, 433172, 2192752, 10726252, 51094203, 238259280, 1092053068, 4934652298, 22034767837, 97407519119, 426916828181 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,11

LINKS

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

Tomás Oliveira e Silva, Animal enumerations on the {4,4} Euclidean tiling

CROSSREFS

Cf. A001419, A057418, A089455, A089456, A089457, A089458.

Sequence in context: A057419 A089664 A121671 * A193368 A109109 A227996

Adjacent sequences:  A089451 A089452 A089453 * A089455 A089456 A089457

KEYWORD

hard,nonn

AUTHOR

Joseph Myers, Nov 04 2003

STATUS

approved

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Last modified December 6 22:42 EST 2021. Contains 349567 sequences. (Running on oeis4.)