A199423 - cp's OEIS frontend

A199423 Greatest prime factor of n and 2*n+1.

n	a(n)
1	3
2	5
3	7
4	3
5	11
6	13
7	7
8	17
9	19
10	7
11	23
12	5
13	13
14	29
15	31
16	11
17	17
18	37
19	19
20	41
21	43
22	11
23	47
24	7
25	17
26	53
27	11
28	19
29	59
30	61
31	31
32	13
33	67
34	23
35	71
36	73
37	37
38	19
39	79
40	5
41	83
42	17
43	43
44	89
45	13
46	31
47	47
48	97
49	11
50	101
51	103
52	13
53	107
54	109
55	37
56	113
57	23
58	29
59	59
60	11
61	61
62	31
63	127
64	43
65	131
66	19

[3, 5, 7, 3, 11, 13, 7, 17, 19, 7, 23, 5, 13, 29, 31, 11, 17, 37, 19, 41, 43, 11, 47, 7, 17, 53, 11, 19, 59, 61, 31, 13, 67, 23, 71, 73, 37, 19, 79, 5, 83, 17, 43, 89, 13, 31, 47, 97, 11, 101, 103, 13, 107, 109, 37, 113, 23, 29, 59, 11, 61, 31, 127, 43, 131, 19]

cp's OEIS Frontend

A199423 Greatest prime factor of n and 2*n+1.

Table of values

List of values

n	a(n)
1	3
2	5
3	7
4	3
5	11
6	13
7	7
8	17
9	19
10	7
11	23
12	5
13	13
14	29
15	31
16	11
17	17
18	37
19	19
20	41
21	43
22	11
23	47
24	7
25	17
26	53
27	11
28	19
29	59
30	61
31	31
32	13
33	67
34	23
35	71
36	73
37	37
38	19
39	79
40	5
41	83
42	17
43	43
44	89
45	13
46	31
47	47
48	97
49	11
50	101
51	103
52	13
53	107
54	109
55	37
56	113
57	23
58	29
59	59
60	11
61	61
62	31
63	127
64	43
65	131
66	19

n	a(n)
1	3
2	5
3	7
4	3
5	11
6	13
7	7
8	17
9	19
10	7
11	23
12	5
13	13
14	29
15	31
16	11
17	17
18	37
19	19
20	41
21	43
22	11
23	47
24	7
25	17
26	53
27	11
28	19
29	59
30	61
31	31
32	13
33	67
34	23
35	71
36	73
37	37
38	19
39	79
40	5
41	83
42	17
43	43
44	89
45	13
46	31
47	47
48	97
49	11
50	101
51	103
52	13
53	107
54	109
55	37
56	113
57	23
58	29
59	59
60	11
61	61
62	31
63	127
64	43
65	131
66	19

n	a(n)
1	3
2	5
3	7
4	3
5	11
6	13
7	7
8	17
9	19
10	7
11	23
12	5
13	13
14	29
15	31
16	11
17	17
18	37
19	19
20	41
21	43
22	11
23	47
24	7
25	17
26	53
27	11
28	19
29	59
30	61
31	31
32	13
33	67
34	23
35	71
36	73
37	37
38	19
39	79
40	5
41	83
42	17
43	43
44	89
45	13
46	31
47	47
48	97
49	11
50	101
51	103
52	13
53	107
54	109
55	37
56	113
57	23
58	29
59	59
60	11
61	61
62	31
63	127
64	43
65	131
66	19