# A337060 (b-file synthesized from sequence entry)
0 1
1 1
2 2
3 8
4 46
5 324
6 2708
7 26424
8 295272
9 3714600
10 51929472
11 798610416
12 13399081584
13 243556758912
14 4767863027328
15 100004300847744
16 2237419620187776
17 53187370914349440
18 1338737435337261312
19 35568441673932566016
20 994744655047298951424
21 29211127285363209561600