# A267981 (b-file synthesized from sequence entry)
0 2
1 6
2 40
3 350
4 3528
5 38808
6 453024
7 5521230
8 69526600
9 898283672
10 11848435872
11 158966514616
12 2163449607200
13 29802622140000
14 414852500188800
15 5827381213589550
16 82510878636707400
17 1176544010190087000
18 16882265852589060000
19 243611096252860135800