A009140 - OEIS

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A009140 as a simple table

n	a(n)
0	1
1	0
2	0
3	0
4	12
5	-120
6	1020
7	-8820
8	82908
9	-867888
10	10145760
11	-131406000
12	1864232832
13	-28656815616
14	473108471472
15	-8332064722800
16	155724385537488
17	-3076215029701248
18	64018830395437056
19	-1399676595110345088

[1,0,0,0,12,-120,1020,-8820,82908,-867888, 10145760,-131406000,1864232832,-28656815616, 473108471472,-8332064722800,155724385537488, -3076215029701248,64018830395437056, -1399676595110345088]