A142979 - OEIS

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A142979 as a simple table

n	a(n)
1	1
2	3
3	13
4	66
5	406
6	2868
7	23220
8	210192
9	2116656
10	23375520
11	281792160
12	3673814400
13	51599514240
14	775673176320
15	12440524320000
16	211848037632000
17	3820318338816000
18	72685037892096000
19	1455838255452672000

[1,3,13,66,406,2868,23220,210192,2116656,23375520, 281792160,3673814400,51599514240,775673176320, 12440524320000,211848037632000,3820318338816000, 72685037892096000,1455838255452672000]