A172990 - cp's OEIS frontend

A172990 a(n) is the smallest k such that the two numbers n^3 +- k are primes.

n	a(n)
2	3
3	4
4	3
5	12
6	17
7	6
8	9
9	10
10	9
11	30
12	5
13	54
14	33
15	14
16	3
17	24
18	11
19	168
20	81
21	20
22	9
23	60
24	17
25	18
26	3
27	80
28	9
29	18
30	73
31	192
32	75
33	14
34	63
35	54
36	7
37	54
38	255
39	38
40	303
41	42
42	11
43	114
44	63
45	4
46	33
47	180
48	5
49	30
50	93
51	28
52	21
53	84
54	115
55	18
56	15
57	40
58	9
59	228
60	61
61	318
62	171
63	4
64	93
65	42
66	5
67	24
68	9
69	70
70	51
71	72
72	49
73	444
74	3

[3, 4, 3, 12, 17, 6, 9, 10, 9, 30, 5, 54, 33, 14, 3, 24, 11, 168, 81, 20, 9, 60, 17, 18, 3, 80, 9, 18, 73, 192, 75, 14, 63, 54, 7, 54, 255, 38, 303, 42, 11, 114, 63, 4, 33, 180, 5, 30, 93, 28, 21, 84, 115, 18, 15, 40, 9, 228, 61, 318, 171, 4, 93, 42, 5, 24, 9, 70, 51, 72, 49, 444, 3]

cp's OEIS Frontend

A172990 a(n) is the smallest k such that the two numbers n^3 +- k are primes.

Table of values

List of values

n	a(n)
2	3
3	4
4	3
5	12
6	17
7	6
8	9
9	10
10	9
11	30
12	5
13	54
14	33
15	14
16	3
17	24
18	11
19	168
20	81
21	20
22	9
23	60
24	17
25	18
26	3
27	80
28	9
29	18
30	73
31	192
32	75
33	14
34	63
35	54
36	7
37	54
38	255
39	38
40	303
41	42
42	11
43	114
44	63
45	4
46	33
47	180
48	5
49	30
50	93
51	28
52	21
53	84
54	115
55	18
56	15
57	40
58	9
59	228
60	61
61	318
62	171
63	4
64	93
65	42
66	5
67	24
68	9
69	70
70	51
71	72
72	49
73	444
74	3

n	a(n)
2	3
3	4
4	3
5	12
6	17
7	6
8	9
9	10
10	9
11	30
12	5
13	54
14	33
15	14
16	3
17	24
18	11
19	168
20	81
21	20
22	9
23	60
24	17
25	18
26	3
27	80
28	9
29	18
30	73
31	192
32	75
33	14
34	63
35	54
36	7
37	54
38	255
39	38
40	303
41	42
42	11
43	114
44	63
45	4
46	33
47	180
48	5
49	30
50	93
51	28
52	21
53	84
54	115
55	18
56	15
57	40
58	9
59	228
60	61
61	318
62	171
63	4
64	93
65	42
66	5
67	24
68	9
69	70
70	51
71	72
72	49
73	444
74	3

n	a(n)
2	3
3	4
4	3
5	12
6	17
7	6
8	9
9	10
10	9
11	30
12	5
13	54
14	33
15	14
16	3
17	24
18	11
19	168
20	81
21	20
22	9
23	60
24	17
25	18
26	3
27	80
28	9
29	18
30	73
31	192
32	75
33	14
34	63
35	54
36	7
37	54
38	255
39	38
40	303
41	42
42	11
43	114
44	63
45	4
46	33
47	180
48	5
49	30
50	93
51	28
52	21
53	84
54	115
55	18
56	15
57	40
58	9
59	228
60	61
61	318
62	171
63	4
64	93
65	42
66	5
67	24
68	9
69	70
70	51
71	72
72	49
73	444
74	3