# A150091 (b-file synthesized from sequence entry) 0 1 1 2 2 6 3 19 4 66 5 243 6 934 7 3702 8 14991 9 61728 10 257760 11 1089242 12 4650510 13 20029566 14 86912034 15 379572697 16 1667173042 17 7359859750 18 32638991596 19 145339269594 20 649585008500 21 2913037850738 22 13103443046264 23 59107608896504 24 267315011379549 25 1211823493295456 26 5505730777691531 27 25065801196926460