# A124889 (b-file synthesized from sequence entry) 0 1 1 2 2 9 3 44 4 235 5 1296 6 7329 7 42104 8 244719 9 1434840 10 8470517 11 50280372 12 299806572 13 1794382548 14 10773855210 15 64865425760 16 391457133672 17 2367314649522 18 14342441005900 19 87035702613500 20 528938145043707 21 3218713327609648