# A056268 (b-file synthesized from sequence entry)
1 0
2 0
3 6
4 36
5 150
6 534
7 1806
8 5760
9 18144
10 55830
11 171006
12 518580
13 1569750
14 4732014
15 14250450
16 42844320
17 128746950
18 386615376
19 1160688606
20 3483582660
21 10454059938
22 31368305694
23 94118013006
24 282378679920
25 847187946000
26 2541662931990
27 7625194813656
28 22875982414740