A238881 - cp's OEIS frontend

A238881 Number of odd primes p < 2n with prime(n(p+1)/2) + n*(p+1)/2 prime.

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

[0, 1, 1, 0, 0, 2, 1, 3, 1, 2, 2, 5, 2, 3, 2, 4, 3, 5, 2, 3, 2, 4, 1, 8, 4, 4, 4, 3, 2, 5, 2, 4, 4, 4, 4, 8, 2, 4, 2, 5, 4, 6, 3, 2, 6, 6, 3, 11, 6, 10, 4, 8, 2, 11, 4, 7, 4, 7, 2, 12, 4, 6, 2, 6, 3, 8, 3, 5, 8, 12, 6, 12, 4, 15, 8, 11, 5, 12, 2, 11]

cp's OEIS Frontend

A238881 Number of odd primes p < 2n with prime(n(p+1)/2) + n*(p+1)/2 prime.

Table of values

List of values

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

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

cp's OEIS Frontend

A238881 Number of odd primes p < 2*n with prime(n*(p+1)/2) + n*(p+1)/2 prime.

Table of values

List of values

A238881 Number of odd primes p < 2n with prime(n(p+1)/2) + n*(p+1)/2 prime.

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