# A077551 (b-file synthesized from sequence entry) 0 0 1 1 2 3 3 5 4 16 5 31 6 105 7 218 8 770 9 1673 10 6096 11 13672 12 51027 13 117194 14 445787 15 1042970 16 4028922 17 9567393 18 37432324 19 89984282 20 355854272