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A019275
as a simple table
n
a(n)
1
1
2
2
3
4
4
38
5
132
6
420
7
1426
8
4834
9
16796
10
58688
11
208012
12
742636
13
2674384
14
9693976
15
35357670
16
129641774
[1,2,4,38,132,420,1426,4834,16796,58688,208012, 742636,2674384,9693976,35357670,129641774]