# A369431 (b-file synthesized from sequence entry) 0 1 1 1 2 2 3 6 4 20 5 66 6 214 7 688 8 2206 9 7070 10 22660 11 72634 12 232830 13 746352 14 2392486 15 7669286 16 24584436 17 78807122 18 252621702 19 809796400 20 2595858574