A054680 - OEIS

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A054680 as a simple table

n	a(n)
2	89
3	1823
4	20809
5	73133
6	989647
7	3250469
8	9065867
9	35677501
10	101341613
11	1383423311
12	11312238283
13	19201563659
14	132932904029
15	534956098463
16	925195153703
17	20151469541389
18	20151469541389
19	102573904861013

[89,1823,20809,73133,989647,3250469,9065867, 35677501,101341613,1383423311,11312238283, 19201563659,132932904029,534956098463, 925195153703,20151469541389,20151469541389, 102573904861013]