A187001 - OEIS

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A187001 as a simple table

n	a(n)
0	1
1	1
2	2
3	12
4	62
5	300
6	1635
7	9413
8	54505
9	321655
10	1938621
11	11834305
12	72975115
13	454385175
14	2852742151
15	18034439209
16	114709370133
17	733605250447
18	4714351916849
19	30426720332601
20	197141722168571
21	1281835943761551

[1,1,2,12,62,300,1635,9413,54505,321655,1938621, 11834305,72975115,454385175,2852742151, 18034439209,114709370133,733605250447, 4714351916849,30426720332601,197141722168571, 1281835943761551]