A066818 - cp's OEIS frontend

A066818 a(n) is the least k such that n + Sum_{i=1..k} A005384(i) is prime; or 0 if none exists.

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

[1, 2, 1, 12, 1, 2, 3, 2, 1, 4, 1, 2, 3, 2, 1, 4, 1, 2, 3, 4, 1, 4, 5, 2, 7, 2, 1, 6, 1, 6, 3, 2, 3, 6, 1, 2, 3, 2, 1, 4, 1, 2, 3, 8, 1, 4, 11, 2, 3, 4, 1, 4, 5, 2, 13, 2, 1, 4, 1, 8, 3, 2, 3, 6, 1, 2, 7, 2, 1, 10, 1, 8, 3, 2, 15, 4, 1, 2, 3, 4, 1, 4, 5, 2, 7, 4]

cp's OEIS Frontend

A066818 a(n) is the least k such that n + Sum_{i=1..k} A005384(i) is prime; or 0 if none exists.

Table of values

List of values

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

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

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