A243290 - cp's OEIS frontend

A243290 The index of the greatest prime dividing the n-th squarefree number: a(n) = A061395(A005117(n)).

n	a(n)
1	0
2	1
3	2
4	3
5	2
6	4
7	3
8	5
9	6
10	4
11	3
12	7
13	8
14	4
15	5
16	9
17	6
18	10
19	3
20	11
21	5
22	7
23	4
24	12
25	8
26	6
27	13
28	4
29	14
30	9
31	15
32	7
33	16
34	5
35	8
36	10
37	17
38	18
39	11
40	6
41	5
42	19
43	9
44	4
45	20
46	21
47	12
48	5
49	6
50	22
51	13
52	23
53	7
54	14
55	10
56	24
57	6
58	11
59	15
60	8
61	25
62	26
63	7
64	27
65	4
66	16
67	28
68	29
69	5
70	12

[0, 1, 2, 3, 2, 4, 3, 5, 6, 4, 3, 7, 8, 4, 5, 9, 6, 10, 3, 11, 5, 7, 4, 12, 8, 6, 13, 4, 14, 9, 15, 7, 16, 5, 8, 10, 17, 18, 11, 6, 5, 19, 9, 4, 20, 21, 12, 5, 6, 22, 13, 23, 7, 14, 10, 24, 6, 11, 15, 8, 25, 26, 7, 27, 4, 16, 28, 29, 5, 12]

cp's OEIS Frontend

A243290 The index of the greatest prime dividing the n-th squarefree number: a(n) = A061395(A005117(n)).

Table of values

List of values

n	a(n)
1	0
2	1
3	2
4	3
5	2
6	4
7	3
8	5
9	6
10	4
11	3
12	7
13	8
14	4
15	5
16	9
17	6
18	10
19	3
20	11
21	5
22	7
23	4
24	12
25	8
26	6
27	13
28	4
29	14
30	9
31	15
32	7
33	16
34	5
35	8
36	10
37	17
38	18
39	11
40	6
41	5
42	19
43	9
44	4
45	20
46	21
47	12
48	5
49	6
50	22
51	13
52	23
53	7
54	14
55	10
56	24
57	6
58	11
59	15
60	8
61	25
62	26
63	7
64	27
65	4
66	16
67	28
68	29
69	5
70	12

n	a(n)
1	0
2	1
3	2
4	3
5	2
6	4
7	3
8	5
9	6
10	4
11	3
12	7
13	8
14	4
15	5
16	9
17	6
18	10
19	3
20	11
21	5
22	7
23	4
24	12
25	8
26	6
27	13
28	4
29	14
30	9
31	15
32	7
33	16
34	5
35	8
36	10
37	17
38	18
39	11
40	6
41	5
42	19
43	9
44	4
45	20
46	21
47	12
48	5
49	6
50	22
51	13
52	23
53	7
54	14
55	10
56	24
57	6
58	11
59	15
60	8
61	25
62	26
63	7
64	27
65	4
66	16
67	28
68	29
69	5
70	12

n	a(n)
1	0
2	1
3	2
4	3
5	2
6	4
7	3
8	5
9	6
10	4
11	3
12	7
13	8
14	4
15	5
16	9
17	6
18	10
19	3
20	11
21	5
22	7
23	4
24	12
25	8
26	6
27	13
28	4
29	14
30	9
31	15
32	7
33	16
34	5
35	8
36	10
37	17
38	18
39	11
40	6
41	5
42	19
43	9
44	4
45	20
46	21
47	12
48	5
49	6
50	22
51	13
52	23
53	7
54	14
55	10
56	24
57	6
58	11
59	15
60	8
61	25
62	26
63	7
64	27
65	4
66	16
67	28
68	29
69	5
70	12