A061395 - cp's OEIS frontend

A061395 Let p be the largest prime factor of n; if p is the k-th prime then set a(n) = k; a(1) = 0 by convention.

n	a(n)
1	0
2	1
3	2
4	1
5	3
6	2
7	4
8	1
9	2
10	3
11	5
12	2
13	6
14	4
15	3
16	1
17	7
18	2
19	8
20	3
21	4
22	5
23	9
24	2
25	3
26	6
27	2
28	4
29	10
30	3
31	11
32	1
33	5
34	7
35	4
36	2
37	12
38	8
39	6
40	3
41	13
42	4
43	14
44	5
45	3
46	9
47	15
48	2
49	4
50	3
51	7
52	6
53	16
54	2
55	5
56	4
57	8
58	10
59	17
60	3
61	18
62	11
63	4
64	1
65	6
66	5
67	19
68	7
69	9
70	4
71	20
72	2
73	21
74	12
75	3
76	8
77	5
78	6
79	22
80	3
81	2
82	13
83	23
84	4
85	7
86	14
87	10
88	5
89	24
90	3
91	6
92	9
93	11
94	15

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

cp's OEIS Frontend

A061395 Let p be the largest prime factor of n; if p is the k-th prime then set a(n) = k; a(1) = 0 by convention.

Table of values

List of values

n	a(n)
1	0
2	1
3	2
4	1
5	3
6	2
7	4
8	1
9	2
10	3
11	5
12	2
13	6
14	4
15	3
16	1
17	7
18	2
19	8
20	3
21	4
22	5
23	9
24	2
25	3
26	6
27	2
28	4
29	10
30	3
31	11
32	1
33	5
34	7
35	4
36	2
37	12
38	8
39	6
40	3
41	13
42	4
43	14
44	5
45	3
46	9
47	15
48	2
49	4
50	3
51	7
52	6
53	16
54	2
55	5
56	4
57	8
58	10
59	17
60	3
61	18
62	11
63	4
64	1
65	6
66	5
67	19
68	7
69	9
70	4
71	20
72	2
73	21
74	12
75	3
76	8
77	5
78	6
79	22
80	3
81	2
82	13
83	23
84	4
85	7
86	14
87	10
88	5
89	24
90	3
91	6
92	9
93	11
94	15

n	a(n)
1	0
2	1
3	2
4	1
5	3
6	2
7	4
8	1
9	2
10	3
11	5
12	2
13	6
14	4
15	3
16	1
17	7
18	2
19	8
20	3
21	4
22	5
23	9
24	2
25	3
26	6
27	2
28	4
29	10
30	3
31	11
32	1
33	5
34	7
35	4
36	2
37	12
38	8
39	6
40	3
41	13
42	4
43	14
44	5
45	3
46	9
47	15
48	2
49	4
50	3
51	7
52	6
53	16
54	2
55	5
56	4
57	8
58	10
59	17
60	3
61	18
62	11
63	4
64	1
65	6
66	5
67	19
68	7
69	9
70	4
71	20
72	2
73	21
74	12
75	3
76	8
77	5
78	6
79	22
80	3
81	2
82	13
83	23
84	4
85	7
86	14
87	10
88	5
89	24
90	3
91	6
92	9
93	11
94	15

n	a(n)
1	0
2	1
3	2
4	1
5	3
6	2
7	4
8	1
9	2
10	3
11	5
12	2
13	6
14	4
15	3
16	1
17	7
18	2
19	8
20	3
21	4
22	5
23	9
24	2
25	3
26	6
27	2
28	4
29	10
30	3
31	11
32	1
33	5
34	7
35	4
36	2
37	12
38	8
39	6
40	3
41	13
42	4
43	14
44	5
45	3
46	9
47	15
48	2
49	4
50	3
51	7
52	6
53	16
54	2
55	5
56	4
57	8
58	10
59	17
60	3
61	18
62	11
63	4
64	1
65	6
66	5
67	19
68	7
69	9
70	4
71	20
72	2
73	21
74	12
75	3
76	8
77	5
78	6
79	22
80	3
81	2
82	13
83	23
84	4
85	7
86	14
87	10
88	5
89	24
90	3
91	6
92	9
93	11
94	15