# A177408 (b-file synthesized from sequence entry)
1 1
2 2
3 8
4 40
5 224
6 1352
7 8576
8 56352
9 380160
10 2617584
11 18320384
12 129950912
13 932114432
14 6749344832
15 49268899840
16 362189529344
17 2678989406208
18 19923485019840
19 148887398711296
20 1117452514604800
21 8419605676818432