A320857 - cp's OEIS frontend

A320857 a(n) = Pi(8,5)(n) + Pi(8,7)(n) - Pi(8,1)(n) - Pi(8,3)(n) where Pi(a,b)(x) denotes the number of primes in the arithmetic progression a*k + b less than or equal to x.

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

[0, 0, -1, -1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, -1, -1, -1, -1, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 2, 2, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 2, 2, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 3, 3, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 2, 2, 2, 2, 2]

cp's OEIS Frontend

A320857 a(n) = Pi(8,5)(n) + Pi(8,7)(n) - Pi(8,1)(n) - Pi(8,3)(n) where Pi(a,b)(x) denotes the number of primes in the arithmetic progression a*k + b less than or equal to x.

Table of values

List of values

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

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

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