%I #15 Sep 14 2024 06:46:43
%S 1,4,16,64,241,920,3384,12585,46471,172226,633138,2333757,8561679,
%T 31462176,115247629,422677188,1546186675,5661378449,20689242550,
%U 75663420126,276279455583,1009416896015,3683274847187,13446591920995,49037278586475,178904588083788,652111697384508,2377810831870022
%N Number of shapes of a Rubik's Snake with n wedges.
%H Peter Aylett, <a href="https://blog.ylett.com/2011/09/rubiks-snake-combinations.html">Rubik's Snake Combinations</a>.
%H Dmytro Fedoriaka, <a href="https://github.com/fedimser/math/blob/master/rubiks-snake/count-shapes.ipynb">Counting Rubik's Snake Shapes</a>.
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Rubik%27s_Snake">Rubik's Snake</a>.
%K nonn
%O 1,2
%A _Dmytro Fedoriaka_, Aug 31 2024