# A177180 (b-file synthesized from sequence entry) 0 1 1 10 2 21 3 144 4 711 5 4747 6 29767 7 205078 8 1409645 9 10043729 10 72216773 11 528438373 12 3903255409 13 29138576719 14 219209569841 15 1661343858524 16 12668020020047 17 97135000445375 18 748428139988567 19 5792032911677831 20 45000447097568843