A180990 - OEIS

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A180990 as a simple table

n	a(n)
1	0
2	0
3	1
4	19
5	721
6	67264
7	16731459
8	11654912023
9	23649647075402
10	144714747782240313
11	2752761136943759699903
12	167080696204654407079545988
13	33078287865123858428157169233610

[0,0,1,19,721,67264,16731459,11654912023, 23649647075402,144714747782240313, 2752761136943759699903, 167080696204654407079545988, 33078287865123858428157169233610]