A236878 - OEIS

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A236878 as a simple table

n	a(n)
1	211
2	669
3	2111
4	7995
5	29673
6	117703
7	462885
8	1868937
9	7534429
10	30744153
11	125576911
12	516317755
13	2126269431
14	8792513827
15	36414484091
16	151240645827
17	628964493529
18	2621050705595
19	10934020192599
20	45682050849053

[211,669,2111,7995,29673,117703,462885,1868937, 7534429,30744153,125576911,516317755,2126269431, 8792513827,36414484091,151240645827,628964493529, 2621050705595,10934020192599,45682050849053]