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%I #26 Feb 17 2023 22:25:32
%S 1,2,6,14,34,82,198,470,1122,2662,6334,14970,35506,83734,198086,
%T 466314,1100818,2587634,6097830,14316402,33687146,79008870,185677006,
%U 435098774,1021404998,2391646494,5609151738,13125214770,30757286802,71928506630
%N Number of fixed snake polyominoes with n cells.
%C This sequence counts snake polyominoes both with and without holes; for example, it counts all four of these 7-cell snakes:
%C ### ## ## ###
%C # # # # # # # #
%C ## ### ### ##
%H Alain Goupil, Marie-Eve Pellerin, and Jérôme de Wouters d'Oplinter, <a href="https://arxiv.org/abs/1307.8432">Partially Directed Snake Polyominoes</a>, arXiv:1307.8432 [math.CO], 2013-2014.
%Y Snake polyominoes by group of symmetries relating shapes considered the same: A002013 (all symmetries), A182644 (translations only), A151514 (rotations and translations), A151527 (horizontal and vertical reflections, rotations of order 2 and translations), A151524 (reflections in either diagonal, rotations of order 2 and translations), A151523 (rotations of order 2 and translations), A151526 (reflections in a horizontal line and translations), A182646 (reflections in a NE-SW diagonal line and translations).
%K nonn
%O 1,2
%A _Joseph Myers_, Nov 24 2010
%E More terms from _Alain Goupil_ and _Jérôme de Wouters_, Jun 21 2014