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A128238
as a simple table
n
a(n)
3
0
4
0
5
1
6
2
7
8
8
26
9
101
10
396
11
1744
12
8531
13
47803
14
308086
15
2300756
16
19909540
17
199365557
[0,0,1,2,8,26,101,396,1744,8531,47803,308086, 2300756,19909540,199365557]