# A149581 (b-file synthesized from sequence entry)
0 1
1 1
2 5
3 15
4 53
5 201
6 773
7 2931
8 11729
9 46807
10 187335
11 762821
12 3124945
13 12808863
14 52974987
15 220149043
16 916268057
17 3831280947
18 16081745835
19 67615084323
20 285092046863
21 1205489408461
22 5105695775689
23 21666537365021
24 92139791974945
25 392421722005823
26 1673781863814147
27 7150683015163675