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A217153
as a simple table
n
a(n)
1
0
2
0
3
0
4
0
5
0
6
0
7
0
8
0
9
0
10
0
11
0
12
0
13
4
14
48
15
264
16
1256
17
5396
18
22540
19
92060
20
370788
[0,0,0,0,0,0,0,0,0,0,0,0,4,48,264,1256,5396,22540, 92060,370788]