A232443 - cp's OEIS frontend

A232443 Number of ways to write n = p + q - pi(q), where p and q are odd primes, 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	2
7	1
8	2
9	2
10	2
11	1
12	2
13	3
14	4
15	2
16	2
17	3
18	3
19	3
20	3
21	3
22	3
23	3
24	4
25	4
26	3
27	3
28	2
29	2
30	5
31	4
32	5
33	5
34	3
35	3
36	4
37	4
38	4
39	5
40	4
41	2
42	6
43	5
44	5
45	5
46	3
47	4
48	8
49	5
50	5
51	6
52	2
53	4
54	7
55	6
56	6
57	5
58	3
59	5
60	7
61	6
62	7
63	6
64	4
65	6
66	6
67	5
68	7
69	5
70	6
71	6
72	7
73	7
74	7
75	6
76	4
77	5
78	7
79	8
80	8
81	7
82	7
83	7
84	7
85	8
86	9
87	5
88	6
89	9
90	9
91	7
92	6
93	7
94	6
95	7
96	8
97	3
98	8
99	9
100	5

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

cp's OEIS Frontend

A232443 Number of ways to write n = p + q - pi(q), where p and q are odd primes, 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	2
7	1
8	2
9	2
10	2
11	1
12	2
13	3
14	4
15	2
16	2
17	3
18	3
19	3
20	3
21	3
22	3
23	3
24	4
25	4
26	3
27	3
28	2
29	2
30	5
31	4
32	5
33	5
34	3
35	3
36	4
37	4
38	4
39	5
40	4
41	2
42	6
43	5
44	5
45	5
46	3
47	4
48	8
49	5
50	5
51	6
52	2
53	4
54	7
55	6
56	6
57	5
58	3
59	5
60	7
61	6
62	7
63	6
64	4
65	6
66	6
67	5
68	7
69	5
70	6
71	6
72	7
73	7
74	7
75	6
76	4
77	5
78	7
79	8
80	8
81	7
82	7
83	7
84	7
85	8
86	9
87	5
88	6
89	9
90	9
91	7
92	6
93	7
94	6
95	7
96	8
97	3
98	8
99	9
100	5

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

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