A138479 - cp's OEIS frontend

A138479 a(n) = smallest prime p such that 2*n + p^2 is another prime, or 0 if no such prime exists.

n	a(n)
1	3
2	3
3	5
4	3
5	3
6	5
7	3
8	5
9	5
10	3
11	3
12	7
13	0
14	3
15	7
16	3
17	3
18	5
19	3
20	7
21	5
22	3
23	5
24	5
25	3
26	3
27	5
28	0
29	3
30	7
31	3
32	3
33	29
34	0
35	3
36	5
37	3
38	5
39	5
40	3
41	5
42	5
43	0
44	3
45	7
46	3
47	3
48	19
49	3
50	3
51	5
52	3
53	5
54	7
55	0
56	5
57	5
58	0
59	3
60	11
61	3
62	5
63	5
64	3
65	3
66	5
67	0
68	11
69	5
70	3
71	3
72	7
73	0
74	3
75	7
76	0
77	3
78	5
79	3
80	11
81	7
82	3
83	5
84	5
85	3
86	3
87	5
88	0
89	7
90	7
91	3
92	3
93	5
94	3
95	3
96	7
97	0
98	11
99	5
100	0

[3, 3, 5, 3, 3, 5, 3, 5, 5, 3, 3, 7, 0, 3, 7, 3, 3, 5, 3, 7, 5, 3, 5, 5, 3, 3, 5, 0, 3, 7, 3, 3, 29, 0, 3, 5, 3, 5, 5, 3, 5, 5, 0, 3, 7, 3, 3, 19, 3, 3, 5, 3, 5, 7, 0, 5, 5, 0, 3, 11, 3, 5, 5, 3, 3, 5, 0, 11, 5, 3, 3, 7, 0, 3, 7, 0, 3, 5, 3, 11, 7, 3, 5, 5, 3, 3, 5, 0, 7, 7, 3, 3, 5, 3, 3, 7, 0, 11, 5, 0]

cp's OEIS Frontend

A138479 a(n) = smallest prime p such that 2*n + p^2 is another prime, or 0 if no such prime exists.

Table of values

List of values

n	a(n)
1	3
2	3
3	5
4	3
5	3
6	5
7	3
8	5
9	5
10	3
11	3
12	7
13	0
14	3
15	7
16	3
17	3
18	5
19	3
20	7
21	5
22	3
23	5
24	5
25	3
26	3
27	5
28	0
29	3
30	7
31	3
32	3
33	29
34	0
35	3
36	5
37	3
38	5
39	5
40	3
41	5
42	5
43	0
44	3
45	7
46	3
47	3
48	19
49	3
50	3
51	5
52	3
53	5
54	7
55	0
56	5
57	5
58	0
59	3
60	11
61	3
62	5
63	5
64	3
65	3
66	5
67	0
68	11
69	5
70	3
71	3
72	7
73	0
74	3
75	7
76	0
77	3
78	5
79	3
80	11
81	7
82	3
83	5
84	5
85	3
86	3
87	5
88	0
89	7
90	7
91	3
92	3
93	5
94	3
95	3
96	7
97	0
98	11
99	5
100	0

n	a(n)
1	3
2	3
3	5
4	3
5	3
6	5
7	3
8	5
9	5
10	3
11	3
12	7
13	0
14	3
15	7
16	3
17	3
18	5
19	3
20	7
21	5
22	3
23	5
24	5
25	3
26	3
27	5
28	0
29	3
30	7
31	3
32	3
33	29
34	0
35	3
36	5
37	3
38	5
39	5
40	3
41	5
42	5
43	0
44	3
45	7
46	3
47	3
48	19
49	3
50	3
51	5
52	3
53	5
54	7
55	0
56	5
57	5
58	0
59	3
60	11
61	3
62	5
63	5
64	3
65	3
66	5
67	0
68	11
69	5
70	3
71	3
72	7
73	0
74	3
75	7
76	0
77	3
78	5
79	3
80	11
81	7
82	3
83	5
84	5
85	3
86	3
87	5
88	0
89	7
90	7
91	3
92	3
93	5
94	3
95	3
96	7
97	0
98	11
99	5
100	0

n	a(n)
1	3
2	3
3	5
4	3
5	3
6	5
7	3
8	5
9	5
10	3
11	3
12	7
13	0
14	3
15	7
16	3
17	3
18	5
19	3
20	7
21	5
22	3
23	5
24	5
25	3
26	3
27	5
28	0
29	3
30	7
31	3
32	3
33	29
34	0
35	3
36	5
37	3
38	5
39	5
40	3
41	5
42	5
43	0
44	3
45	7
46	3
47	3
48	19
49	3
50	3
51	5
52	3
53	5
54	7
55	0
56	5
57	5
58	0
59	3
60	11
61	3
62	5
63	5
64	3
65	3
66	5
67	0
68	11
69	5
70	3
71	3
72	7
73	0
74	3
75	7
76	0
77	3
78	5
79	3
80	11
81	7
82	3
83	5
84	5
85	3
86	3
87	5
88	0
89	7
90	7
91	3
92	3
93	5
94	3
95	3
96	7
97	0
98	11
99	5
100	0