A236511 - cp's OEIS frontend

A236511 a(n) = |{0 < k < n: p = 3*phi(k) + phi(n-k) - 1, p + 2, p + 6 and p + 8 are all prime}|, 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	1
12	1
13	2
14	0
15	1
16	0
17	1
18	1
19	0
20	1
21	1
22	1
23	0
24	1
25	0
26	0
27	0
28	0
29	0
30	0
31	0
32	0
33	0
34	0
35	0
36	0
37	0
38	0
39	0
40	0
41	0
42	0
43	0
44	1
45	0
46	0
47	0
48	1
49	0
50	0
51	0
52	1
53	0
54	0
55	0
56	1
57	1
58	1
59	1
60	2
61	0
62	0
63	0
64	0
65	1
66	1
67	2
68	1
69	1
70	1
71	1
72	0
73	2
74	2
75	2
76	2
77	2
78	2
79	0
80	2
81	0
82	4
83	4
84	2
85	1
86	3
87	4
88	2
89	2
90	3
91	0
92	1
93	3
94	2
95	3
96	1
97	4
98	4
99	3
100	1

[0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 2, 0, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 1, 2, 0, 0, 0, 0, 1, 1, 2, 1, 1, 1, 1, 0, 2, 2, 2, 2, 2, 2, 0, 2, 0, 4, 4, 2, 1, 3, 4, 2, 2, 3, 0, 1, 3, 2, 3, 1, 4, 4, 3, 1]

cp's OEIS Frontend

A236511 a(n) = |{0 < k < n: p = 3*phi(k) + phi(n-k) - 1, p + 2, p + 6 and p + 8 are all prime}|, 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	1
12	1
13	2
14	0
15	1
16	0
17	1
18	1
19	0
20	1
21	1
22	1
23	0
24	1
25	0
26	0
27	0
28	0
29	0
30	0
31	0
32	0
33	0
34	0
35	0
36	0
37	0
38	0
39	0
40	0
41	0
42	0
43	0
44	1
45	0
46	0
47	0
48	1
49	0
50	0
51	0
52	1
53	0
54	0
55	0
56	1
57	1
58	1
59	1
60	2
61	0
62	0
63	0
64	0
65	1
66	1
67	2
68	1
69	1
70	1
71	1
72	0
73	2
74	2
75	2
76	2
77	2
78	2
79	0
80	2
81	0
82	4
83	4
84	2
85	1
86	3
87	4
88	2
89	2
90	3
91	0
92	1
93	3
94	2
95	3
96	1
97	4
98	4
99	3
100	1

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

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