# A175900 (b-file synthesized from sequence entry)
0 1
1 2
2 9
3 57
4 411
5 3150
6 25274
7 209719
8 1784909
9 15495058
10 136672624
11 1221370092
12 11034687854
13 100623850938
14 924917387599
15 8560734224711
16 79717622732369
17 746322905220237
18 7020573752016609
19 66324819580927731
20 629004053328092981