A237720 - cp's OEIS frontend

A237720 Number of primes p <= (n+1)/2 with floor( sqrt(n-p) ) prime.

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

[0, 0, 0, 0, 0, 1, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 3, 2, 2, 2, 2, 1, 1, 2, 2, 2, 3, 2, 3, 3, 4, 4, 4, 4, 5, 5, 5, 4, 4, 3, 4, 3, 4, 4, 4, 3, 4, 3, 3, 4, 5, 4, 5, 4, 5, 6, 6, 5, 6, 7, 8, 8, 8, 7, 7, 5, 6, 5, 5]

cp's OEIS Frontend

A237720 Number of primes p <= (n+1)/2 with floor( sqrt(n-p) ) prime.

Table of values

List of values

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

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

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