A133830 - cp's OEIS frontend

A133830 Least positive number k < n such that the binary trinomial 1 + 2^n + 2^k is prime, or 0 if there is no such k.

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

[1, 1, 1, 2, 1, 1, 0, 3, 3, 2, 1, 4, 5, 1, 1, 11, 1, 6, 5, 4, 7, 3, 9, 0, 17, 15, 1, 15, 1, 6, 0, 4, 9, 14, 13, 3, 11, 25, 0, 6, 7, 0, 17, 7, 15, 2, 0, 30, 23, 6, 21, 2, 33, 1, 0, 3, 0, 14, 5, 6, 21, 19, 0, 30, 3, 1, 5, 34, 19, 26, 17, 19, 17, 5, 33, 15, 23, 27, 33, 4, 3, 26, 1, 39, 35, 19, 9, 18]

cp's OEIS Frontend

A133830 Least positive number k < n such that the binary trinomial 1 + 2^n + 2^k is prime, or 0 if there is no such k.

Table of values

List of values

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

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

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