A027489 - OEIS

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A027489 as a simple table

n	a(n)
1	1
2	7
3	176
4	10746
5	1297704
6	272866980
7	91570835040
8	46034917019280
9	33038572997888640
10	32591683412232799680
11	42861143959833044563200
12	73273310483627217731644800
13	159431451667479363623304936960

[1,7,176,10746,1297704,272866980,91570835040, 46034917019280,33038572997888640, 32591683412232799680,42861143959833044563200, 73273310483627217731644800, 159431451667479363623304936960]