A080958 - OEIS

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A080958 as a simple table

n	a(n)
1	2
2	1
3	11
4	14
5	214
6	444
7	8868
8	25584
9	633456
10	2342880
11	69317280
12	312888960
13	10773578880
14	57424792320
15	2256224544000
16	13869128448000
17	612385401600000
18	4264876094976000
19	209080119919104000
20	1627055289796608000

[2,1,11,14,214,444,8868,25584,633456,2342880, 69317280,312888960,10773578880,57424792320, 2256224544000,13869128448000,612385401600000, 4264876094976000,209080119919104000, 1627055289796608000]