A269850 - cp's OEIS frontend

A269850 a(n) = number of integers k <= n for which prime(k+1)-prime(k) is a multiple of three.

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

[0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 2, 2, 3, 4, 4, 5, 5, 5, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 9, 10, 10, 11, 12, 12, 12, 12, 12, 12, 13, 14, 14, 14, 14, 15, 15, 15, 16, 17, 18, 18, 19, 19, 19, 19, 19, 19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 22, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 25, 25, 26, 26, 26, 26, 26, 27]

cp's OEIS Frontend

A269850 a(n) = number of integers k <= n for which prime(k+1)-prime(k) is a multiple of three.

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

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

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