A188001 - OEIS

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A188001 as a simple table

n	a(n)
1	1
2	9
3	12
4	88
5	270
6	1587
7	7674
8	43750
9	242128
10	1393159
11	8045324
12	46987016
13	275921190
14	1631855528
15	9700469624
16	57950502071
17	34778286544
18	2096134083792
19	12683659236886
20	77033023135718
21	469480677007150

[1,9,12,88,270,1587,7674,43750,242128,1393159, 8045324,46987016,275921190,1631855528,9700469624, 57950502071,34778286544,2096134083792, 12683659236886,77033023135718,469480677007150]