# A012715 (b-file synthesized from sequence entry)
0 0
1 1
2 2
3 6
4 24
5 160
6 1120
7 9296
8 79744
9 791232
10 8303488
11 98662784
12 1234416128
13 17090231808
14 247660907520
15 3911062116352
16 64395491606528
17 1142963925405696
18 21081499860049920
19 415641154415091712