A212716 - cp's OEIS frontend

A212716 Denominator of Sum_{k=1..n} 1/lambda(k), where lambda(k) is the Carmichael's lambda function.

n	a(n)
1	1
2	1
3	2
4	1
5	4
6	4
7	12
8	12
9	12
10	6
11	15
12	30
13	60
14	60
15	15
16	60
17	240
18	80
19	720
20	720
21	720
22	720
23	7920
24	7920
25	1584
26	1584
27	1584
28	1584
29	11088
30	11088
31	55440
32	55440
33	55440
34	13860
35	6930
36	3465
37	13860
38	13860
39	6930
40	13860
41	27720
42	27720
43	27720
44	27720
45	27720
46	27720
47	637560
48	637560

[1, 1, 2, 1, 4, 4, 12, 12, 12, 6, 15, 30, 60, 60, 15, 60, 240, 80, 720, 720, 720, 720, 7920, 7920, 1584, 1584, 1584, 1584, 11088, 11088, 55440, 55440, 55440, 13860, 6930, 3465, 13860, 13860, 6930, 13860, 27720, 27720, 27720, 27720, 27720, 27720, 637560, 637560]

cp's OEIS Frontend

A212716 Denominator of Sum_{k=1..n} 1/lambda(k), where lambda(k) is the Carmichael's lambda function.

Table of values

List of values