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.

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.