A278635 - cp's OEIS frontend

A278635 Least x such that ax-1 and bx-1 are simultaneously prime and n (sequence index) is the position of rational a/b (lowest form) in the triangular array A226314(n)/A054531(n).

n	a(n)
1	1
2	3
3	3
4	4
5	2
6	4
7	3
8	2
9	1
10	3
11	4
12	4
13	4
14	6
15	4
16	3
17	1
18	4
19	4
20	4
21	3
22	6
23	2
24	2
25	2
26	6
27	2
28	6
29	3
30	6
31	1
32	2
33	4
34	2
35	6
36	3
37	6
38	2
39	2
40	2
41	6
42	1
43	2
44	6
45	6
46	3
47	4
48	2
49	6
50	2
51	4
52	2
53	6
54	2
55	3
56	4
57	4
58	4
59	12
60	4
61	4
62	12
63	4
64	10
65	18
66	4
67	4
68	2
69	2
70	2
71	4
72	4
73	2
74	4
75	12
76	4
77	4
78	4
79	8
80	24
81	8
82	8
83	18
84	8
85	14
86	24
87	8
88	8
89	18

[1, 3, 3, 4, 2, 4, 3, 2, 1, 3, 4, 4, 4, 6, 4, 3, 1, 4, 4, 4, 3, 6, 2, 2, 2, 6, 2, 6, 3, 6, 1, 2, 4, 2, 6, 3, 6, 2, 2, 2, 6, 1, 2, 6, 6, 3, 4, 2, 6, 2, 4, 2, 6, 2, 3, 4, 4, 4, 12, 4, 4, 12, 4, 10, 18, 4, 4, 2, 2, 2, 4, 4, 2, 4, 12, 4, 4, 4, 8, 24, 8, 8, 18, 8, 14, 24, 8, 8, 18]

cp's OEIS Frontend

A278635 Least x such that ax-1 and bx-1 are simultaneously prime and n (sequence index) is the position of rational a/b (lowest form) in the triangular array A226314(n)/A054531(n).

Table of values

List of values

n	a(n)
1	1
2	3
3	3
4	4
5	2
6	4
7	3
8	2
9	1
10	3
11	4
12	4
13	4
14	6
15	4
16	3
17	1
18	4
19	4
20	4
21	3
22	6
23	2
24	2
25	2
26	6
27	2
28	6
29	3
30	6
31	1
32	2
33	4
34	2
35	6
36	3
37	6
38	2
39	2
40	2
41	6
42	1
43	2
44	6
45	6
46	3
47	4
48	2
49	6
50	2
51	4
52	2
53	6
54	2
55	3
56	4
57	4
58	4
59	12
60	4
61	4
62	12
63	4
64	10
65	18
66	4
67	4
68	2
69	2
70	2
71	4
72	4
73	2
74	4
75	12
76	4
77	4
78	4
79	8
80	24
81	8
82	8
83	18
84	8
85	14
86	24
87	8
88	8
89	18

n	a(n)
1	1
2	3
3	3
4	4
5	2
6	4
7	3
8	2
9	1
10	3
11	4
12	4
13	4
14	6
15	4
16	3
17	1
18	4
19	4
20	4
21	3
22	6
23	2
24	2
25	2
26	6
27	2
28	6
29	3
30	6
31	1
32	2
33	4
34	2
35	6
36	3
37	6
38	2
39	2
40	2
41	6
42	1
43	2
44	6
45	6
46	3
47	4
48	2
49	6
50	2
51	4
52	2
53	6
54	2
55	3
56	4
57	4
58	4
59	12
60	4
61	4
62	12
63	4
64	10
65	18
66	4
67	4
68	2
69	2
70	2
71	4
72	4
73	2
74	4
75	12
76	4
77	4
78	4
79	8
80	24
81	8
82	8
83	18
84	8
85	14
86	24
87	8
88	8
89	18

n	a(n)
1	1
2	3
3	3
4	4
5	2
6	4
7	3
8	2
9	1
10	3
11	4
12	4
13	4
14	6
15	4
16	3
17	1
18	4
19	4
20	4
21	3
22	6
23	2
24	2
25	2
26	6
27	2
28	6
29	3
30	6
31	1
32	2
33	4
34	2
35	6
36	3
37	6
38	2
39	2
40	2
41	6
42	1
43	2
44	6
45	6
46	3
47	4
48	2
49	6
50	2
51	4
52	2
53	6
54	2
55	3
56	4
57	4
58	4
59	12
60	4
61	4
62	12
63	4
64	10
65	18
66	4
67	4
68	2
69	2
70	2
71	4
72	4
73	2
74	4
75	12
76	4
77	4
78	4
79	8
80	24
81	8
82	8
83	18
84	8
85	14
86	24
87	8
88	8
89	18