A240131 - cp's OEIS frontend

A240131 Least k such that prime(n)^2 + k^2 is prime, or 0 if none.

n	a(n)
1	1
2	2
3	2
4	2
5	4
6	2
7	2
8	6
9	8
10	4
11	4
12	2
13	4
14	8
15	2
16	10
17	6
18	10
19	2
20	6
21	2
22	4
23	18
24	4
25	2
26	10
27	2
28	10
29	4
30	18
31	8
32	16
33	2
34	10
35	14
36	4
37	10
38	2
39	2
40	10
41	4
42	6
43	4
44	2
45	8
46	16
47	4
48	18
49	8
50	4
51	2
52	10
53	16
54	14
55	18
56	8
57	10
58	6
59	2
60	4
61	8
62	2
63	2
64	4
65	2
66	2
67	6
68	20
69	2
70	14
71	8
72	10
73	8
74	2
75	6
76	12
77	4
78	18
79	4
80	6
81	14
82	4
83	6
84	12
85	4
86	28
87	10
88	12
89	6
90	2
91	12
92	14
93	2
94	6
95	4
96	2
97	14
98	14
99	10
100	6

[1, 2, 2, 2, 4, 2, 2, 6, 8, 4, 4, 2, 4, 8, 2, 10, 6, 10, 2, 6, 2, 4, 18, 4, 2, 10, 2, 10, 4, 18, 8, 16, 2, 10, 14, 4, 10, 2, 2, 10, 4, 6, 4, 2, 8, 16, 4, 18, 8, 4, 2, 10, 16, 14, 18, 8, 10, 6, 2, 4, 8, 2, 2, 4, 2, 2, 6, 20, 2, 14, 8, 10, 8, 2, 6, 12, 4, 18, 4, 6, 14, 4, 6, 12, 4, 28, 10, 12, 6, 2, 12, 14, 2, 6, 4, 2, 14, 14, 10, 6]

cp's OEIS Frontend

A240131 Least k such that prime(n)^2 + k^2 is prime, or 0 if none.

Table of values

List of values

n	a(n)
1	1
2	2
3	2
4	2
5	4
6	2
7	2
8	6
9	8
10	4
11	4
12	2
13	4
14	8
15	2
16	10
17	6
18	10
19	2
20	6
21	2
22	4
23	18
24	4
25	2
26	10
27	2
28	10
29	4
30	18
31	8
32	16
33	2
34	10
35	14
36	4
37	10
38	2
39	2
40	10
41	4
42	6
43	4
44	2
45	8
46	16
47	4
48	18
49	8
50	4
51	2
52	10
53	16
54	14
55	18
56	8
57	10
58	6
59	2
60	4
61	8
62	2
63	2
64	4
65	2
66	2
67	6
68	20
69	2
70	14
71	8
72	10
73	8
74	2
75	6
76	12
77	4
78	18
79	4
80	6
81	14
82	4
83	6
84	12
85	4
86	28
87	10
88	12
89	6
90	2
91	12
92	14
93	2
94	6
95	4
96	2
97	14
98	14
99	10
100	6

n	a(n)
1	1
2	2
3	2
4	2
5	4
6	2
7	2
8	6
9	8
10	4
11	4
12	2
13	4
14	8
15	2
16	10
17	6
18	10
19	2
20	6
21	2
22	4
23	18
24	4
25	2
26	10
27	2
28	10
29	4
30	18
31	8
32	16
33	2
34	10
35	14
36	4
37	10
38	2
39	2
40	10
41	4
42	6
43	4
44	2
45	8
46	16
47	4
48	18
49	8
50	4
51	2
52	10
53	16
54	14
55	18
56	8
57	10
58	6
59	2
60	4
61	8
62	2
63	2
64	4
65	2
66	2
67	6
68	20
69	2
70	14
71	8
72	10
73	8
74	2
75	6
76	12
77	4
78	18
79	4
80	6
81	14
82	4
83	6
84	12
85	4
86	28
87	10
88	12
89	6
90	2
91	12
92	14
93	2
94	6
95	4
96	2
97	14
98	14
99	10
100	6

n	a(n)
1	1
2	2
3	2
4	2
5	4
6	2
7	2
8	6
9	8
10	4
11	4
12	2
13	4
14	8
15	2
16	10
17	6
18	10
19	2
20	6
21	2
22	4
23	18
24	4
25	2
26	10
27	2
28	10
29	4
30	18
31	8
32	16
33	2
34	10
35	14
36	4
37	10
38	2
39	2
40	10
41	4
42	6
43	4
44	2
45	8
46	16
47	4
48	18
49	8
50	4
51	2
52	10
53	16
54	14
55	18
56	8
57	10
58	6
59	2
60	4
61	8
62	2
63	2
64	4
65	2
66	2
67	6
68	20
69	2
70	14
71	8
72	10
73	8
74	2
75	6
76	12
77	4
78	18
79	4
80	6
81	14
82	4
83	6
84	12
85	4
86	28
87	10
88	12
89	6
90	2
91	12
92	14
93	2
94	6
95	4
96	2
97	14
98	14
99	10
100	6