A375386 - cp's OEIS frontend

A375386 a(n) is the common difference in the longest arithmetic progression of primes ending in prime(n). If there is more than one such arithmetic progression, the smallest difference is chosen.

n	a(n)
2	1
3	2
4	2
5	4
6	2
7	6
8	6
9	6
10	6
11	12
12	6
13	12
14	12
15	18
16	12
17	6
18	24
19	24
20	12
21	6
22	6
23	12
24	18
25	18
26	30
27	30
28	18
29	6
30	30
31	30
32	30
33	24
34	36
35	48
36	24
37	30
38	12
39	18
40	42
41	6
42	54
43	54
44	42
45	48
46	60
47	30
48	42
49	30
50	66
51	42
52	66
53	30
54	60
55	30
56	12
57	6
58	30
59	48
60	84
61	60
62	60
63	78
64	60
65	102
66	60
67	60
68	30
69	78
70	36
71	60
72	90
73	18
74	90
75	6
76	72
77	96
78	30
79	54

[1, 2, 2, 4, 2, 6, 6, 6, 6, 12, 6, 12, 12, 18, 12, 6, 24, 24, 12, 6, 6, 12, 18, 18, 30, 30, 18, 6, 30, 30, 30, 24, 36, 48, 24, 30, 12, 18, 42, 6, 54, 54, 42, 48, 60, 30, 42, 30, 66, 42, 66, 30, 60, 30, 12, 6, 30, 48, 84, 60, 60, 78, 60, 102, 60, 60, 30, 78, 36, 60, 90, 18, 90, 6, 72, 96, 30, 54]

cp's OEIS Frontend

A375386 a(n) is the common difference in the longest arithmetic progression of primes ending in prime(n). If there is more than one such arithmetic progression, the smallest difference is chosen.

Table of values

List of values

n	a(n)
2	1
3	2
4	2
5	4
6	2
7	6
8	6
9	6
10	6
11	12
12	6
13	12
14	12
15	18
16	12
17	6
18	24
19	24
20	12
21	6
22	6
23	12
24	18
25	18
26	30
27	30
28	18
29	6
30	30
31	30
32	30
33	24
34	36
35	48
36	24
37	30
38	12
39	18
40	42
41	6
42	54
43	54
44	42
45	48
46	60
47	30
48	42
49	30
50	66
51	42
52	66
53	30
54	60
55	30
56	12
57	6
58	30
59	48
60	84
61	60
62	60
63	78
64	60
65	102
66	60
67	60
68	30
69	78
70	36
71	60
72	90
73	18
74	90
75	6
76	72
77	96
78	30
79	54

n	a(n)
2	1
3	2
4	2
5	4
6	2
7	6
8	6
9	6
10	6
11	12
12	6
13	12
14	12
15	18
16	12
17	6
18	24
19	24
20	12
21	6
22	6
23	12
24	18
25	18
26	30
27	30
28	18
29	6
30	30
31	30
32	30
33	24
34	36
35	48
36	24
37	30
38	12
39	18
40	42
41	6
42	54
43	54
44	42
45	48
46	60
47	30
48	42
49	30
50	66
51	42
52	66
53	30
54	60
55	30
56	12
57	6
58	30
59	48
60	84
61	60
62	60
63	78
64	60
65	102
66	60
67	60
68	30
69	78
70	36
71	60
72	90
73	18
74	90
75	6
76	72
77	96
78	30
79	54

n	a(n)
2	1
3	2
4	2
5	4
6	2
7	6
8	6
9	6
10	6
11	12
12	6
13	12
14	12
15	18
16	12
17	6
18	24
19	24
20	12
21	6
22	6
23	12
24	18
25	18
26	30
27	30
28	18
29	6
30	30
31	30
32	30
33	24
34	36
35	48
36	24
37	30
38	12
39	18
40	42
41	6
42	54
43	54
44	42
45	48
46	60
47	30
48	42
49	30
50	66
51	42
52	66
53	30
54	60
55	30
56	12
57	6
58	30
59	48
60	84
61	60
62	60
63	78
64	60
65	102
66	60
67	60
68	30
69	78
70	36
71	60
72	90
73	18
74	90
75	6
76	72
77	96
78	30
79	54