# A121681 (b-file synthesized from sequence entry)
0 1
1 1
2 4
3 19
4 131
5 1136
6 11670
7 138727
8 1864711
9 27843874
10 456081803
11 8114074563
12 155519173031
13 3189879446235
14 69629136671356
15 1609836360587087
16 39262941548917619
17 1006616998791629666
18 27044968746461571213