# A052557 (b-file synthesized from sequence entry)
0 1
1 0
2 0
3 6
4 24
5 120
6 1440
7 15120
8 161280
9 2177280
10 32659200
11 518918400
12 9101030400
13 174356582400
14 3574309939200
15 78460462080000
16 1841205510144000
17 45883678224384000
18 1210048630382592000