# A003104 (b-file synthesized from sequence entry)
1 1
2 1
3 2
4 4
5 10
6 24
7 67
8 182
9 520
10 1474
11 4248
12 12196
13 35168
14 101226
15 291565
16 838764
17 2412033
18 6929754
19 19896915
20 57084939