A275319 - cp's OEIS frontend

A275319 Numbers n such that n concatenated with n+1 is not a prime.

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

[1, 3, 4, 5, 7, 9, 10, 11, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 37, 38, 39, 40, 41, 43, 44, 45, 46, 47, 48, 49, 51, 52, 53, 54, 55, 57, 58, 59, 60, 61, 63, 64, 65, 66, 67, 69, 70, 71, 72, 73, 74, 75, 76]

cp's OEIS Frontend

A275319 Numbers n such that n concatenated with n+1 is not a prime.

Table of values

List of values

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

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

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