A087274 - cp's OEIS frontend

A087274 Prime index of the largest prime factor of 3*prime(n)+1.

n	a(n)
1	4
2	3
3	1
4	5
5	7
6	3
7	6
8	10
9	4
10	5
11	15
12	4
13	11
14	6
15	20
16	3
17	24
18	9
19	26
20	28
21	5
22	7
23	3
24	19
25	21
26	8
27	11
28	9
29	13
30	7
31	43
32	45
33	27
34	8
35	4
36	49
37	17
38	4
39	54
40	6
41	57
42	7
43	13
44	10
45	12
46	9
47	66
48	19
49	11
50	14
51	4
52	72
53	42
54	10
55	44
56	22
57	26
58	12
59	6
60	47
61	7
62	5
63	89
64	91
65	15
66	7
67	20
68	9
69	98
70	32
71	16
72	5
73	10
74	4
75	104
76	9
77	21
78	35
79	14
80	63
81	12
82	22

[4, 3, 1, 5, 7, 3, 6, 10, 4, 5, 15, 4, 11, 6, 20, 3, 24, 9, 26, 28, 5, 7, 3, 19, 21, 8, 11, 9, 13, 7, 43, 45, 27, 8, 4, 49, 17, 4, 54, 6, 57, 7, 13, 10, 12, 9, 66, 19, 11, 14, 4, 72, 42, 10, 44, 22, 26, 12, 6, 47, 7, 5, 89, 91, 15, 7, 20, 9, 98, 32, 16, 5, 10, 4, 104, 9, 21, 35, 14, 63, 12, 22]

cp's OEIS Frontend

A087274 Prime index of the largest prime factor of 3*prime(n)+1.

Table of values

List of values

n	a(n)
1	4
2	3
3	1
4	5
5	7
6	3
7	6
8	10
9	4
10	5
11	15
12	4
13	11
14	6
15	20
16	3
17	24
18	9
19	26
20	28
21	5
22	7
23	3
24	19
25	21
26	8
27	11
28	9
29	13
30	7
31	43
32	45
33	27
34	8
35	4
36	49
37	17
38	4
39	54
40	6
41	57
42	7
43	13
44	10
45	12
46	9
47	66
48	19
49	11
50	14
51	4
52	72
53	42
54	10
55	44
56	22
57	26
58	12
59	6
60	47
61	7
62	5
63	89
64	91
65	15
66	7
67	20
68	9
69	98
70	32
71	16
72	5
73	10
74	4
75	104
76	9
77	21
78	35
79	14
80	63
81	12
82	22

n	a(n)
1	4
2	3
3	1
4	5
5	7
6	3
7	6
8	10
9	4
10	5
11	15
12	4
13	11
14	6
15	20
16	3
17	24
18	9
19	26
20	28
21	5
22	7
23	3
24	19
25	21
26	8
27	11
28	9
29	13
30	7
31	43
32	45
33	27
34	8
35	4
36	49
37	17
38	4
39	54
40	6
41	57
42	7
43	13
44	10
45	12
46	9
47	66
48	19
49	11
50	14
51	4
52	72
53	42
54	10
55	44
56	22
57	26
58	12
59	6
60	47
61	7
62	5
63	89
64	91
65	15
66	7
67	20
68	9
69	98
70	32
71	16
72	5
73	10
74	4
75	104
76	9
77	21
78	35
79	14
80	63
81	12
82	22

n	a(n)
1	4
2	3
3	1
4	5
5	7
6	3
7	6
8	10
9	4
10	5
11	15
12	4
13	11
14	6
15	20
16	3
17	24
18	9
19	26
20	28
21	5
22	7
23	3
24	19
25	21
26	8
27	11
28	9
29	13
30	7
31	43
32	45
33	27
34	8
35	4
36	49
37	17
38	4
39	54
40	6
41	57
42	7
43	13
44	10
45	12
46	9
47	66
48	19
49	11
50	14
51	4
52	72
53	42
54	10
55	44
56	22
57	26
58	12
59	6
60	47
61	7
62	5
63	89
64	91
65	15
66	7
67	20
68	9
69	98
70	32
71	16
72	5
73	10
74	4
75	104
76	9
77	21
78	35
79	14
80	63
81	12
82	22