# A136631 (b-file synthesized from sequence entry)
0 1
1 1
2 2
3 6
4 28
5 177
6 1449
7 14869
8 185230
9 2738962
10 47287352
11 939759621
12 21241309681
13 540698975061
14 15370957337418
15 484433735633218
16 16817886069720724
17 639545680226171989
18 26507567678760284105