A200045 - OEIS

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A200045 as a simple table

n	a(n)
1	4
2	16
3	252
4	64
5	3912
6	228984
7	256
8	59928
9	12870096
10	2545607472
11	1024
12	906912
13	696448224
14	465659203104
15	272454472598400
16	4096
17	13571712
18	36376835616
19	79102304162784
20	140221913588582784

[4,16,252,64,3912,228984,256,59928,12870096, 2545607472,1024,906912,696448224,465659203104, 272454472598400,4096,13571712,36376835616, 79102304162784,140221913588582784]