# A187874 (b-file synthesized from sequence entry)
0 3
1 3
2 5
3 11
4 31
5 131
6 733
7 5059
8 40351
9 362903
10 3628819
11 39916817
12 479001643
13 6227020873
14 87178291241
15 1307674368149
16 20922789888041
17 355687428096053
18 6402373705728061
19 121645100408832109
20 2432902008176640037
21 51090942171709440037