A242753 - cp's OEIS frontend

A242753 Number of ordered ways to write n = k + m with 0 < k <= m such that the inverse of k mod prime(k) among 1, ..., prime(k) - 1 is prime and the inverse of m mod prime(m) among 1, ..., prime(m) - 1 is also prime.

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

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

cp's OEIS Frontend

A242753 Number of ordered ways to write n = k + m with 0 < k <= m such that the inverse of k mod prime(k) among 1, ..., prime(k) - 1 is prime and the inverse of m mod prime(m) among 1, ..., prime(m) - 1 is also prime.

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

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

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