A276988 - cp's OEIS frontend

A276988 a(n) is the least k such that 10*k+prime(n) is composite.

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

[1, 3, 1, 2, 1, 2, 1, 2, 1, 1, 2, 2, 1, 2, 1, 1, 1, 2, 1, 1, 2, 2, 1, 1, 2, 1, 2, 1, 1, 1, 2, 1, 1, 2, 1, 1, 2, 2, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 2, 1, 2, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 2, 2, 1, 1, 1, 1, 2, 1, 2, 1, 2, 2, 1, 1, 2, 1, 1]

cp's OEIS Frontend

A276988 a(n) is the least k such that 10*k+prime(n) is composite.

Table of values

List of values

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

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

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