A232463 - cp's OEIS frontend

A232463 Number of ways to write n = p + q - pi(q), where p and q are odd primes not exceeding n, and pi(q) is the number of primes not exceeding q.

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

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

cp's OEIS Frontend

A232463 Number of ways to write n = p + q - pi(q), where p and q are odd primes not exceeding n, and pi(q) is the number of primes not exceeding q.

Table of values

List of values

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

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

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