# A153687 (b-file synthesized from sequence entry) 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 23 9 56 10 77 11 103 12 320 13 1477 14 1821 15 2992 16 15290 17 180168 18 410498 19 548816 20 672732 21 2601223