# A148476 (b-file synthesized from sequence entry) 0 1 1 1 2 2 3 6 4 20 5 67 6 238 7 889 8 3430 9 13502 10 54133 11 220602 12 912169 13 3814549 14 16105873 15 68586793 16 294388261 17 1272134186 18 5530081563 19 24168691099 20 106150861556 21 468293726986 22 2074232732996 23 9221208846420 24 41133693548902 25 184061536758043 26 825997748283384 27 3716645799512423 28 16765083601178960