# A156411 (b-file synthesized from sequence entry)
0 1
1 120
2 8940
3 216680
4 1939740
5 7574400
6 18391220
7 48340560
8 133072650
9 294400160
10 636803010
11 1521100320
12 3164432181
13 5269056120
14 9096418860
15 18579992000
16 34459271550
17 49721066400
18 70412760560
19 126260708400
20 215977376730