A157569 - OEIS

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A157569 as a simple table

n	a(n)
2	1
3	9
4	234
5	13330
6	759255
7	39386151
8	1941592492
9	100065421116
10	4986199986795
11	221853806154915
12	9037873481632974
13	346801773380423010
14	12750860059402207015
15	453349862010556020825
16	15650738757439717731720

[1,9,234,13330,759255,39386151,1941592492, 100065421116,4986199986795,221853806154915, 9037873481632974,346801773380423010, 12750860059402207015,453349862010556020825, 15650738757439717731720]