A235912 - cp's OEIS frontend

A235912 a(n) = |{0 < k < n - 2: 2m + 1, m(m-1) - prime(m) and m*(m+1) - prime(m) are all prime with m = phi(k) + phi(n-k)/2}|, where phi(.) is Euler's totient function.

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

[0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 2, 3, 2, 4, 2, 6, 5, 6, 7, 4, 8, 7, 8, 8, 11, 7, 12, 9, 9, 12, 5, 14, 10, 9, 9, 9, 9, 7, 8, 11, 9, 8, 7, 14, 8, 6, 9, 5, 5, 9, 11, 3, 9, 6, 13, 8, 8, 6, 7, 6, 5, 4, 3, 1, 5, 5, 5, 6, 5, 7, 7, 4, 7, 11, 8, 3, 5, 3, 10, 4, 4, 3, 9, 2, 4, 4, 5, 8, 12, 13, 4, 9, 5, 11, 5, 12, 7, 4, 4]

cp's OEIS Frontend

A235912 a(n) = |{0 < k < n - 2: 2m + 1, m(m-1) - prime(m) and m*(m+1) - prime(m) are all prime with m = phi(k) + phi(n-k)/2}|, where phi(.) is Euler's totient function.

Table of values

List of values

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

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

cp's OEIS Frontend

A235912 a(n) = |{0 < k < n - 2: 2*m + 1, m*(m-1) - prime(m) and m*(m+1) - prime(m) are all prime with m = phi(k) + phi(n-k)/2}|, where phi(.) is Euler's totient function.

Table of values

List of values

A235912 a(n) = |{0 < k < n - 2: 2m + 1, m(m-1) - prime(m) and m*(m+1) - prime(m) are all prime with m = phi(k) + phi(n-k)/2}|, where phi(.) is Euler's totient function.

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