# A074031 (b-file synthesized from sequence entry)
1 1
2 0
3 2
4 0
5 15
6 40
7 153
8 480
9 1841
10 6528
11 23901
12 87040
13 322875
14 1198080
15 4474738
16 16773120
17 63164175
18 238605640
19 904213989
20 3435921408
21 13089461538
22 49977753600
23 191219550297
24 733007052640
25 2814750270420
26 10825959997440
27 41699998413248
28 160842834247680