# A161881 (b-file synthesized from sequence entry)
0 1
1 1
2 2
3 8
4 46
5 333
6 2822
7 26884
8 280778
9 3162129
10 37962174
11 481796692
12 6424120440
13 89561323131
14 1300606338522
15 19614272779492
16 306422062160964
17 4948682216714809
18 82474329755007710
19 1416291364674413764
20 25027636488359996744
21 454585893218323184316