A004123 - OEIS

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A004123 as a simple table

n	a(n)
1	1
2	2
3	10
4	74
5	730
6	9002
7	133210
8	2299754
9	45375130
10	1007179562
11	24840104410
12	673895590634
13	19944372341530
14	639455369290922
15	22079273878443610
16	816812844197444714
17	32232133532123179930
18	1351401783010933015082

[1,2,10,74,730,9002,133210,2299754,45375130, 1007179562,24840104410,673895590634, 19944372341530,639455369290922,22079273878443610, 816812844197444714,32232133532123179930, 1351401783010933015082]