# A026031 (b-file synthesized from sequence entry)
2 1
3 6
4 28
5 120
6 494
7 1988
8 7888
9 31008
10 121125
11 471086
12 1826660
13 7068360
14 27313650
15 105452700
16 406923360
17 1569869760
18 6056194410
19 23366193084
20 90173331960
21 348102883184
22 1344324544156
23 5193831553416
24 20075820280544
25 77637309982400