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%I #24 Jan 19 2023 11:02:37
%S 1,1,2,5,10,24,53,126,289,686,1604,3792,8925,21051,49638,116858,
%T 275480,647573,1525113,3580673,8423334,19755938,46422915,108783480,
%U 255359883,597932342,1402308318,3281352516,7689369625,17982241557,42108302007,98422076879,230322745835
%N Number of 1-sided snake polyominoes with n cells.
%C A snake polyomino has 2 cells with 1 neighbor each, and (n-2) cells with 2 neighbors each. - _Arthur O'Dwyer_, Dec 12 2022
%H Arthur O'Dwyer, <a href="https://quuxplusone.github.io/blog/2022/12/08/polyomino-snakes/">Polyomino strips, snakes, and ouroboroi</a>, Dec 10 2022.
%H Ed Pegg, Jr., <a href="http://demonstrations.wolfram.com/PolyformExplorer/">Illustrations of polyforms</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Polyomino.html">Polyomino</a>
%Y A002013 counts 2-sided (free) snake polyominoes.
%Y A359068 gives the number of 1-sided strip polyominoes (that is, snakes without holes) with n cells; A359068(n) < A151514(n) for n >= 7.
%K nonn,hard,more
%O 1,3
%A _Ed Pegg Jr_, May 13 2009
%E a(15)-a(23) from _Joseph Myers_, Nov 22 2010
%E a(24)-a(29) from _Arthur O'Dwyer_, Dec 10 2022
%E a(30)-a(33) from _Arthur O'Dwyer_, Jan 19 2023
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