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A333313
Number of 2-sided strip polyominoes with n cells and no holes.
2
1, 1, 1, 2, 3, 7, 13, 30, 64, 150, 338, 794, 1836, 4313, 10067, 23621, 55313, 129647, 303720, 711078, 1665037, 3894282, 9111343, 21290577, 49770844, 116206114, 271435025, 633298969, 1478178004, 3446626028, 8039424324, 18734704111, 43673728357, 101723730306
OFFSET
0,4
COMMENTS
This sequence first differs from A002013 at n = 7. An example of a polyomino counted by A002013, but not by this sequence, is:
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LINKS
CROSSREFS
Cf. A002013.
Sequence in context: A113884 A070218 A048456 * A262829 A071899 A242389
KEYWORD
nonn
AUTHOR
Peter Kagey, Mar 14 2020
EXTENSIONS
a(16)-a(26) from John Mason, Sep 15 2022
a(27)-a(33) from Arthur O'Dwyer's blog added by Andrey Zabolotskiy, Jun 20 2024
STATUS
approved