# A027327 (b-file synthesized from sequence entry) 0 1 1 3 2 12 3 36 4 108 5 324 6 972 7 2916 8 8748 9 26244 10 78732 11 236196 12 708588 13 2125764 14 6377292 15 19131876 16 57395628 17 172186884 18 516560652 19 1549681956 20 4649045868 21 13947137604 22 41841412812 23 125524238436 24 376572715308