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A218961
as a simple table
n
a(n)
0
1
1
1
2
1
3
1
4
5
5
21
6
91
7
421
8
3011
9
18467
10
105911
11
1183931
12
11717443
13
126700003
[1,1,1,1,5,21,91,421,3011,18467,105911,1183931, 11717443,126700003]