A227305 - OEIS

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A227305 as a simple table

n	a(n)
1	2
2	3
3	5
4	6
5	10
6	19
7	52
8	118
9	1054
10	3201
11	8586
12	9802
13	16120
14	60556
15	140698
16	145216
17	11273536
18	29886160
19	44868748
20	8748377956
21	325377469696
22	2368739714188

[2,3,5,6,10,19,52,118,1054,3201,8586,9802,16120, 60556,140698,145216,11273536,29886160,44868748, 8748377956,325377469696,2368739714188]