# A149305 (b-file synthesized from sequence entry) 0 1 1 1 2 4 3 11 4 48 5 157 6 707 7 2547 8 11728 9 44793 10 209515 11 830425 12 3928512 13 15975975 14 76204982 15 315911451 16 1516208552 17 6380856199 18 30770097293 19 131072626339 20 634440420834 21 2729589294471 22 13252591412098 23 57494028166843 24 279850008278954 25 1222697025739077 26 5964136075927073 27 26217164510751277