A032201 - OEIS

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A032201 as a simple table

n	a(n)
1	2
2	2
3	5
4	13
5	40
6	128
7	457
8	1660
9	6308
10	24409
11	96363
12	385535
13	1561706
14	6387135
15	26347199
16	109471366
17	457758461
18	1924845582
19	8134171456
20	34526723986
21	147139513066
22	629314845284
23	2700401538933
24	11622130671430

[2,2,5,13,40,128,457,1660,6308,24409,96363,385535, 1561706,6387135,26347199,109471366,457758461, 1924845582,8134171456,34526723986,147139513066, 629314845284,2700401538933,11622130671430]