A032004 - OEIS

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A032004 as a simple table

n	a(n)
1	1
2	1
3	1
4	7
5	15
6	105
7	855
8	7855
9	55975
10	560065
11	8413815
12	92433795
13	1445733485
14	21748130145
15	378156976785
16	6718626421035
17	128657800331555
18	2540367695055365
19	57535394030907155
20	1264457062012294015

[1,1,1,7,15,105,855,7855,55975,560065,8413815, 92433795,1445733485,21748130145,378156976785, 6718626421035,128657800331555,2540367695055365, 57535394030907155,1264457062012294015]