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A293261
Number of fixed polyominoes without holes that have a width and height of n.
2
1, 5, 106, 6074, 943340, 419355340, 554485727288, 2208574156731474, 26609978139626497670, 973224195603423767343946, 108342096917091380628767818812, 36763211016528549310068224122368860, 38044287043749436284594644308861499605492
OFFSET
1,2
COMMENTS
Equivalently, the number of cycles on an (n+1) X (n+1) grid that touch each of the four outside edges.
LINKS
Andrey Zabolotskiy, Table of n, a(n) for n = 1..16
Anthony J. Guttmann and Iwan Jensen, Effect of Confinement: Polygons in Strips, Slabs and Rectangles, in: Polygons, Polyominoes and Polycubes, LNP 775, Springer, 2009. See Table 10.2 on p. 239.
CROSSREFS
Main diagonal of A232103.
Cf. A268404.
Sequence in context: A059490 A204109 A093979 * A324230 A142479 A204110
KEYWORD
nonn
AUTHOR
Andrew Howroyd, Oct 04 2017
STATUS
approved