# A168990 (b-file synthesized from sequence entry)
0 1
1 25
2 600
3 14400
4 345600
5 8294400
6 199065600
7 4777574400
8 114661785600
9 2751882854400
10 66045188505600
11 1585084524134400
12 38042028579225600
13 913008685901414400
14 21912208461633945600
15 525893003079214694400