

A216951


Let S be a string of n 2's and 3's, with curling number k, which means S = XY^k where k is maximized; a(n) = number of S for which X must be taken to be the empty string.


2



2, 2, 2, 4, 2, 8, 2, 10, 8, 14, 2, 40, 2, 40, 32, 88, 2, 192, 2, 324, 100, 564, 2, 1356, 32, 2226, 370, 4564, 2, 9656, 2, 17944, 1450, 35424, 152, 74182, 2, 141628, 5774, 284342, 2, 578022, 2, 1134518, 23576, 2265394, 2, 4580468, 128, 9062280, 92236, 18129626
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OFFSET

1,1


COMMENTS

See A216730 for definition of curling number.


LINKS



EXAMPLE

For n=6, there are 8 strings S that satisfy the condition:
222222, k=6, Y=2
223223, k=2, Y=223
232232, k=2, Y=232
232323, k=3, Y=23
and 4 more by exchanging 2 and 3. Note that 233233 with k=2 is not on the list, because we could choose X empty, Y=233 or X=2332, Y=3, and the latter avoids taking X to be empty.


CROSSREFS



KEYWORD

nonn


AUTHOR



EXTENSIONS



STATUS

approved



