# A220180 (b-file synthesized from sequence entry)
0 1
1 1
2 4
3 42
4 924
5 36300
6 2265960
7 206703840
8 25945444560
9 4287205253520
10 901822916010240
11 235245784759302240
12 74515547291697610560
13 28171404151229273014080
14 12529985068482904127064960
15 6476871523103017023955968000
16 3850268179365489288889549267200