A023578 - cp's OEIS frontend

A023578 Least odd prime divisor of prime(n)+3, or 1 if prime(n)+3 is a power of 2.

n	a(n)
1	5
2	3
3	1
4	5
5	7
6	1
7	5
8	11
9	13
10	1
11	17
12	5
13	11
14	23
15	5
16	7
17	31
18	1
19	5
20	37
21	19
22	41
23	43
24	23
25	5
26	13
27	53
28	5
29	7
30	29
31	5
32	67
33	5
34	71
35	19
36	7
37	5
38	83
39	5
40	11
41	7
42	23
43	97
44	7
45	5
46	101
47	107
48	113
49	5
50	29
51	59
52	11
53	61
54	127
55	5
56	7
57	17
58	137
59	5
60	71
61	11
62	37
63	5
64	157
65	79
66	5
67	167
68	5
69	5
70	11
71	89
72	181
73	5
74	47
75	191

[5, 3, 1, 5, 7, 1, 5, 11, 13, 1, 17, 5, 11, 23, 5, 7, 31, 1, 5, 37, 19, 41, 43, 23, 5, 13, 53, 5, 7, 29, 5, 67, 5, 71, 19, 7, 5, 83, 5, 11, 7, 23, 97, 7, 5, 101, 107, 113, 5, 29, 59, 11, 61, 127, 5, 7, 17, 137, 5, 71, 11, 37, 5, 157, 79, 5, 167, 5, 5, 11, 89, 181, 5, 47, 191]

cp's OEIS Frontend

A023578 Least odd prime divisor of prime(n)+3, or 1 if prime(n)+3 is a power of 2.

Table of values

List of values

n	a(n)
1	5
2	3
3	1
4	5
5	7
6	1
7	5
8	11
9	13
10	1
11	17
12	5
13	11
14	23
15	5
16	7
17	31
18	1
19	5
20	37
21	19
22	41
23	43
24	23
25	5
26	13
27	53
28	5
29	7
30	29
31	5
32	67
33	5
34	71
35	19
36	7
37	5
38	83
39	5
40	11
41	7
42	23
43	97
44	7
45	5
46	101
47	107
48	113
49	5
50	29
51	59
52	11
53	61
54	127
55	5
56	7
57	17
58	137
59	5
60	71
61	11
62	37
63	5
64	157
65	79
66	5
67	167
68	5
69	5
70	11
71	89
72	181
73	5
74	47
75	191

n	a(n)
1	5
2	3
3	1
4	5
5	7
6	1
7	5
8	11
9	13
10	1
11	17
12	5
13	11
14	23
15	5
16	7
17	31
18	1
19	5
20	37
21	19
22	41
23	43
24	23
25	5
26	13
27	53
28	5
29	7
30	29
31	5
32	67
33	5
34	71
35	19
36	7
37	5
38	83
39	5
40	11
41	7
42	23
43	97
44	7
45	5
46	101
47	107
48	113
49	5
50	29
51	59
52	11
53	61
54	127
55	5
56	7
57	17
58	137
59	5
60	71
61	11
62	37
63	5
64	157
65	79
66	5
67	167
68	5
69	5
70	11
71	89
72	181
73	5
74	47
75	191

n	a(n)
1	5
2	3
3	1
4	5
5	7
6	1
7	5
8	11
9	13
10	1
11	17
12	5
13	11
14	23
15	5
16	7
17	31
18	1
19	5
20	37
21	19
22	41
23	43
24	23
25	5
26	13
27	53
28	5
29	7
30	29
31	5
32	67
33	5
34	71
35	19
36	7
37	5
38	83
39	5
40	11
41	7
42	23
43	97
44	7
45	5
46	101
47	107
48	113
49	5
50	29
51	59
52	11
53	61
54	127
55	5
56	7
57	17
58	137
59	5
60	71
61	11
62	37
63	5
64	157
65	79
66	5
67	167
68	5
69	5
70	11
71	89
72	181
73	5
74	47
75	191