A130412 - OEIS

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A130412 as a simple table

n	a(n)
1	2
2	5
3	140
4	105
5	2310
6	15015
7	120120
8	85085
9	9699690
10	4849845
11	446185740
12	557732175
13	3346393050
14	48522699225
15	24067258815600
16	1504203675975
17	3008407351950
18	55655536011075
19	222622144044300
20	2281876976454075

[2,5,140,105,2310,15015,120120,85085,9699690, 4849845,446185740,557732175,3346393050, 48522699225,24067258815600,1504203675975, 3008407351950,55655536011075,222622144044300, 2281876976454075]