513392domain: NAppears in sequencesNumber of sequences of n 2's and 3's with curling number 2 and which have the form XY^2 with Y = 2.at n=21A217832Number of sequences of n 2's and 3's with curling number 2 and which have the form XY^2 where Y has length 1 (so Y is 2 or 3).at n=20A217931