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A131487 a(n) is the number of polyominoes with n edges. 0
0, 0, 0, 1, 0, 0, 1, 0, 0, 2, 0, 1, 4, 0, 1, 11, 1, 7, 27, 4, 21, 85 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,10

COMMENTS

n-celled polyomino with perimeter p has (4n+p)/2 edges. The maximum number of edges in an n-celled polyomino is 3n+1.

LINKS

Table of n, a(n) for n=1..22.

Isoperimetrical Polyominoes at Poly Pages

CROSSREFS

Cf. A000105: Number of polyominoes (or square animals) with n cells. A057730: Number of polyominoes (A000105) with perimeter 2n. A131482: a(n) is the number of n-celled polyominoes with perimeter 2n+2.

Sequence in context: A121462 A271466 A218581 * A230747 A181670 A261251

Adjacent sequences:  A131484 A131485 A131486 * A131488 A131489 A131490

KEYWORD

hard,more,nonn

AUTHOR

Tanya Khovanova, Jul 28 2007

STATUS

approved

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Last modified June 28 14:30 EDT 2017. Contains 288838 sequences.