# A208091 (b-file synthesized from sequence entry) 0 1 1 11 2 3 3 4 4 6 5 8 6 38 7 24 8 32 9 18 10 48 11 138 12 20 13 588 14 144 15 252 16 5520 17 168 18 7200 19 2400 20 2850