# A248964 (b-file synthesized from sequence entry)
0 1
1 4
2 40
3 160
4 5600
5 896
6 19200
7 76800
8 14784000
9 19712000
10 512512000
11 186368000
12 19568640000
13 6021120000
14 20889600000
15 7798784000
16 71310131200000
17 16778854400000
18 503365632000000
19 15138816000000
20 221798793216000000
21 6035341312000000