# A165559 (b-file synthesized from sequence entry)
2 1
3 1
4 4
5 4
6 20
7 20
8 240
9 1440
10 10080
11 10080
12 161280
13 161280
14 1451520
15 11612160
16 371589120
17 371589120
18 7803371520
19 7803371520
20 187280916480
21 1872809164800
22 24346519142400
23 24346519142400
24 1071246842265600
25 10712468422656000