# A294517 (b-file synthesized from sequence entry)
0 3
1 42
2 154
3 4620
4 87780
5 672980
6 18170460
7 1126568520
8 1126568520
9 14645390760
10 629751802680
11 29598334725960
12 503171690341320
13 100634338068264
14 29687129730137880
15 59374259460275760
16 3978075383838475920
17 282443352252531790320
18 1412216761262658951600
19 111565124139750057176400
20 9259905303599254745641200