# A275540 (b-file synthesized from sequence entry)
0 1
1 0
2 1
3 5
4 27
5 129
6 761
7 5137
8 40695
9 363815
10 3632629
11 39927183
12 479047667
13 6227155921
14 87178936305
15 1307676395009
16 20922800209903
17 355687462555407
18 6402373891522541
19 121645101063561055
20 2432902011892531179