# A371039 (b-file synthesized from sequence entry)
0 1
1 1
2 2
3 12
4 72
5 480
6 4680
7 52920
8 645120
9 9313920
10 153014400
11 2720995200
12 53428636800
13 1154333980800
14 26847281260800
15 671610658118400
16 18064388076134400
17 517898679679180800
18 15763026427487539200
19 508612525689235968000
20 17329554246181072896000