# A027288 (b-file synthesized from sequence entry) 0 1 1 4 2 12 3 46 4 145 5 552 6 1820 7 6918 8 23562 9 89645 10 312664 11 1191885 12 4232345 13 16170728 14 58229100 15 222997812 16 811985790 17 3116622123 18 11451785640 19 44047806725 20 163072988442 21 628465576101 22 2341484487832 23 9040083756276 24 33863310322100 25 130957152428622