# A218684 (b-file synthesized from sequence entry)
0 1
1 0
2 1
3 2
4 7
5 18
6 96
7 260
8 1851
9 5270
10 46515
11 137942
12 1447202
13 4433772
14 53787706
15 169169912
16 2326986783
17 7477418982
18 114916173009
19 375898894514
20 6380455164161
21 21185872231238
22 393499602818322
23 1323362744628080
24 26691270481453228
25 90755667374332324