# A274461 (b-file synthesized from sequence entry)
0 1
1 4
2 8
3 72
4 144
5 3600
6 10800
7 21600
8 1058400
9 2116800
10 6350400
11 768398400
12 3841992000
13 7683984000
14 1298593296000
15 3895779888000
16 7791559776000
17 2251760775264000
18 15762325426848000
19 5690199479092128000
20 11380398958184256000
21 6020231048879471424000
22 30101155244397357120000
23 90303465733192071360000