# A159036 (b-file synthesized from sequence entry) 0 0 1 1 2 4 3 13 4 38 5 108 6 306 7 868 8 2464 9 6996 10 19864 11 56400 12 160136 13 454672 14 1290944 15 3665360 16 10407008 17 29548480 18 83896608 19 238206528 20 676336640 21 1920313664 22 5452321152 23 15480703232 24 43954155648 25 124798451968 26 354338591744 27 1006068870400