A238577 - cp's OEIS frontend

A238577 a(n) = |{0 < k <= n: p(n)q(k)r(k) + 1 is prime}|, where p(.), q(.) and r(.) are given by A000041, A000009 and A047967 respectively.

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

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

cp's OEIS Frontend

A238577 a(n) = |{0 < k <= n: p(n)q(k)r(k) + 1 is prime}|, where p(.), q(.) and r(.) are given by A000041, A000009 and A047967 respectively.

Table of values

List of values

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

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

cp's OEIS Frontend

A238577 a(n) = |{0 < k <= n: p(n)*q(k)*r(k) + 1 is prime}|, where p(.), q(.) and r(.) are given by A000041, A000009 and A047967 respectively.

Table of values

List of values

A238577 a(n) = |{0 < k <= n: p(n)q(k)r(k) + 1 is prime}|, where p(.), q(.) and r(.) are given by A000041, A000009 and A047967 respectively.

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