# A002060 (b-file synthesized from sequence entry)
7 4
8 60
9 550
10 4004
11 25480
12 148512
13 813960
14 4263600
15 21573816
16 106234700
17 511801290
18 2421810300
19 11289642000
20 51967090560
21 236635858800
22 1067518772640
23 4776759725400
24 21221827263000
25 93687293423724
26 411270420524040
27 1796296260955504
28 7809983743284800
29 33816739954270000