# A232994 (b-file synthesized from sequence entry)
3 0
4 0
5 240
6 10368
7 395136
8 15728640
9 680244480
10 32256000000
11 1676208500736
12 95105071448064
13 5863863973294080
14 390979732037959680
15 28060084800000000000
16 2158269056624017539072
17 177206054288314912014336
18 15475174380451335052984320
19 1432670891083019685105500160
20 140187732541440000000000000000