# A186720 (b-file synthesized from sequence entry)
1 1
2 4
3 144
4 3600
5 1270080
6 153679680
7 519437318400
8 150117385017600
9 221193371393280
10 6450247552370862240000
11 5424658191543895143840000
12 20852386088294732932920960000
13 28546916554875489385168794240000
14 6855338104106528236638391873920000
15 12675520154492970709544386574878080000