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A001403
as a simple table
n
a(n)
1
0
2
0
3
0
4
0
5
0
6
0
7
1
8
1
9
3
10
10
11
31
12
229
13
2036
14
21399
15
245342
16
3004881
17
38904499
18
530452205
19
7640941062
[0,0,0,0,0,0,1,1,3,10,31,229,2036,21399,245342, 3004881,38904499,530452205,7640941062]