A208989 - OEIS

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A208989 as a simple table

n	a(n)
1	1
2	3
3	7
4	33
5	159
6	874
7	4935
8	28816
9	171413
10	1036611
11	6350875
12	39346156
13	246076193
14	1551630136
15	9853551873
16	62966367376
17	404595868611

[1,3,7,33,159,874,4935,28816,171413,1036611, 6350875,39346156,246076193,1551630136,9853551873, 62966367376,404595868611]