# A302190 (b-file synthesized from sequence entry)
0 0
1 2
2 -1
3 2
4 -6
5 24
6 -120
7 720
8 -5040
9 40320
10 -362880
11 3628800
12 -39916800
13 479001600
14 -6227020800
15 87178291200
16 -1307674368000
17 20922789888000
18 -355687428096000
19 6402373705728000
20 -121645100408832000
21 2432902008176640000
22 -51090942171709440000