# A166198 (b-file synthesized from sequence entry) 0 1 1 4 2 2 3 3 4 14 5 30 6 89 7 553 8 1588 9 8865 10 104510 11 444424 12 4173156 13 81325310 14 652489468 15 10459516337 16 342881668736 17 4580518588744 18 125220290825340 19 7022575980797573 20 156952369257684587