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A067675
Number of fixed convex polyominoes with n cells.
7
1, 2, 6, 19, 59, 176, 502, 1374, 3630, 9312, 23320, 57279, 138536, 331032, 783630, 1841867, 4306172, 10028276, 23288394, 53974959, 124925967, 288878550, 667602492, 1542254655, 3562000916, 8225719574, 18994263354, 43858728367, 101270779744, 233836327750, 539935689810
OFFSET
1,2
REFERENCES
Steven R. Finch, Mathematical Constants, Encyclopedia of Mathematics and its Applications, vol. 94, Cambridge University Press, 2003, Section 5.19, p. 380.
LINKS
Ruben Grønning Spaans, Table of n, a(n) for n = 1..1000
Gadi Aleksandrowicz, Andrei Asinowski and Gill Barequet, A polyominoes-permutations injection and tree-like convex polyominoes, Journal of Combinatorial Theory, Series A, Volume 119, Issue 3, April 2012, Pages 503-520.
M. Bousquet-Mélou and J.-M. Fédou, The generating function of convex polyominoes: the resolution of a q-differential system, Discrete Math. 137 (1995) 53-75.
Ruben Grønning Spaans, C program.
V. M. Zhuravlev, Horizontally-convex polyiamonds and their generating functions, Mat. Pros. 17 (2013), 107-129 (in Russian).
FORMULA
a(n) ~ c * d^n, where d = A276994 = 2.309138593330494731098720305017212531911814472581628401694402900284456440748..., c = 2.91959850971360705538470951565133568591516894147305658630679268977185945... . - Vaclav Kotesovec, Sep 27 2016
CROSSREFS
Cf. A006958, A067676 (fixed directed convex polyominoes), A191148 (fixed line-convex polycubes in 3 dimensions), A276994.
Sequence in context: A307564 A308240 A328658 * A037512 A111277 A014346
KEYWORD
nonn
AUTHOR
Steven Finch, Feb 04 2002
EXTENSIONS
Six more terms from Ruben Grønning Spaans, Sep 20 2014
STATUS
approved