A233296 - cp's OEIS frontend

A233296 a(n) = |{0 < k < n: k*prime(n-k) + 1 is prime}|.

n	a(n)
1	0
2	1
3	1
4	2
5	1
6	2
7	2
8	2
9	2
10	3
11	3
12	4
13	2
14	2
15	5
16	4
17	1
18	6
19	1
20	2
21	5
22	4
23	4
24	4
25	3
26	3
27	2
28	4
29	6
30	5
31	4
32	5
33	6
34	7
35	7
36	6
37	5
38	8
39	6
40	4
41	5
42	7
43	8
44	4
45	6
46	7
47	6
48	10
49	7
50	4
51	8
52	11
53	9
54	11
55	6
56	5
57	5
58	8
59	8
60	10
61	5
62	7
63	10
64	10
65	11
66	7
67	6
68	6
69	12
70	6
71	10
72	11
73	6
74	11
75	7
76	11
77	8
78	12
79	7
80	7
81	9
82	13
83	9
84	10
85	14
86	7
87	13
88	8
89	10
90	11
91	9
92	14
93	10
94	14
95	17
96	14
97	13
98	8
99	12
100	12

[0, 1, 1, 2, 1, 2, 2, 2, 2, 3, 3, 4, 2, 2, 5, 4, 1, 6, 1, 2, 5, 4, 4, 4, 3, 3, 2, 4, 6, 5, 4, 5, 6, 7, 7, 6, 5, 8, 6, 4, 5, 7, 8, 4, 6, 7, 6, 10, 7, 4, 8, 11, 9, 11, 6, 5, 5, 8, 8, 10, 5, 7, 10, 10, 11, 7, 6, 6, 12, 6, 10, 11, 6, 11, 7, 11, 8, 12, 7, 7, 9, 13, 9, 10, 14, 7, 13, 8, 10, 11, 9, 14, 10, 14, 17, 14, 13, 8, 12, 12]

cp's OEIS Frontend

A233296 a(n) = |{0 < k < n: k*prime(n-k) + 1 is prime}|.

Table of values

List of values

n	a(n)
1	0
2	1
3	1
4	2
5	1
6	2
7	2
8	2
9	2
10	3
11	3
12	4
13	2
14	2
15	5
16	4
17	1
18	6
19	1
20	2
21	5
22	4
23	4
24	4
25	3
26	3
27	2
28	4
29	6
30	5
31	4
32	5
33	6
34	7
35	7
36	6
37	5
38	8
39	6
40	4
41	5
42	7
43	8
44	4
45	6
46	7
47	6
48	10
49	7
50	4
51	8
52	11
53	9
54	11
55	6
56	5
57	5
58	8
59	8
60	10
61	5
62	7
63	10
64	10
65	11
66	7
67	6
68	6
69	12
70	6
71	10
72	11
73	6
74	11
75	7
76	11
77	8
78	12
79	7
80	7
81	9
82	13
83	9
84	10
85	14
86	7
87	13
88	8
89	10
90	11
91	9
92	14
93	10
94	14
95	17
96	14
97	13
98	8
99	12
100	12

n	a(n)
1	0
2	1
3	1
4	2
5	1
6	2
7	2
8	2
9	2
10	3
11	3
12	4
13	2
14	2
15	5
16	4
17	1
18	6
19	1
20	2
21	5
22	4
23	4
24	4
25	3
26	3
27	2
28	4
29	6
30	5
31	4
32	5
33	6
34	7
35	7
36	6
37	5
38	8
39	6
40	4
41	5
42	7
43	8
44	4
45	6
46	7
47	6
48	10
49	7
50	4
51	8
52	11
53	9
54	11
55	6
56	5
57	5
58	8
59	8
60	10
61	5
62	7
63	10
64	10
65	11
66	7
67	6
68	6
69	12
70	6
71	10
72	11
73	6
74	11
75	7
76	11
77	8
78	12
79	7
80	7
81	9
82	13
83	9
84	10
85	14
86	7
87	13
88	8
89	10
90	11
91	9
92	14
93	10
94	14
95	17
96	14
97	13
98	8
99	12
100	12

n	a(n)
1	0
2	1
3	1
4	2
5	1
6	2
7	2
8	2
9	2
10	3
11	3
12	4
13	2
14	2
15	5
16	4
17	1
18	6
19	1
20	2
21	5
22	4
23	4
24	4
25	3
26	3
27	2
28	4
29	6
30	5
31	4
32	5
33	6
34	7
35	7
36	6
37	5
38	8
39	6
40	4
41	5
42	7
43	8
44	4
45	6
46	7
47	6
48	10
49	7
50	4
51	8
52	11
53	9
54	11
55	6
56	5
57	5
58	8
59	8
60	10
61	5
62	7
63	10
64	10
65	11
66	7
67	6
68	6
69	12
70	6
71	10
72	11
73	6
74	11
75	7
76	11
77	8
78	12
79	7
80	7
81	9
82	13
83	9
84	10
85	14
86	7
87	13
88	8
89	10
90	11
91	9
92	14
93	10
94	14
95	17
96	14
97	13
98	8
99	12
100	12