# A094434 (b-file synthesized from sequence entry)
1 0
2 2
3 12
4 60
5 288
6 1368
7 6480
8 30672
9 145152
10 686880
11 3250368
12 15380928
13 72783360
14 344414592
15 1629787392
16 7712236800
17 36494696448
18 172694757888
19 817200368640
20 3867033664512
21 18298999775232
22 86591796664320
23 409756781334528