A123801 - OEIS

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A123801 as a simple table

n	a(n)
1	1
2	4
3	7
4	31
5	76
6	365
7	920
8	4691
9	12695
10	65708
11	184458
12	967195
13	2798734
14	14837523
15	43829052
16	234029147
17	703643181

[1,4,7,31,76,365,920,4691,12695,65708,184458, 967195,2798734,14837523,43829052,234029147, 703643181]