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A250587 as a simple table

n a(n)
1 639
2 3641
3 17718
4 79415
5 333355
6 1347397
7 5284985
8 20355558
9 77281643
10 290814703
11 1086782674
12 4044122800
13 14999512012
14 55523390718
15 205218626587
16 757840894067
17 2796700223479
18 10316975388347
19 38048035207739
20 140296439330149

[639,3641,17718,79415,333355,1347397,5284985,
 20355558,77281643,290814703,1086782674,4044122800,
 14999512012,55523390718,205218626587,757840894067,
 2796700223479,10316975388347,38048035207739,
 140296439330149]

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Last modified December 8 03:17 EST 2021. Contains 349590 sequences. (Running on oeis4.)