A235859 - cp's OEIS frontend

A235859 Define a(4)=3, then a(n+1) is the smallest prime P such that a(n) <= P < 2n with 2n-P=Q prime and, if not possible, a(n+1) is the smallest prime P such that P < a(n) < 2n with 2n-P=Q prime.

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

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

cp's OEIS Frontend

A235859 Define a(4)=3, then a(n+1) is the smallest prime P such that a(n) <= P < 2n with 2n-P=Q prime and, if not possible, a(n+1) is the smallest prime P such that P < a(n) < 2n with 2n-P=Q prime.

Table of values

List of values

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

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

cp's OEIS Frontend

A235859 Define a(4)=3, then a(n+1) is the smallest prime P such that a(n) <= P < 2*n with 2*n-P=Q prime and, if not possible, a(n+1) is the smallest prime P such that P < a(n) < 2*n with 2*n-P=Q prime.

Table of values

List of values

A235859 Define a(4)=3, then a(n+1) is the smallest prime P such that a(n) <= P < 2n with 2n-P=Q prime and, if not possible, a(n+1) is the smallest prime P such that P < a(n) < 2n with 2n-P=Q prime.

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