A231577 - cp's OEIS frontend

A231577 Number of ways to write n = x + y (x, y > 0) with 2^x + y*(y+1)/2 prime.

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

[0, 1, 2, 1, 2, 2, 2, 2, 4, 3, 2, 2, 3, 3, 3, 3, 6, 3, 4, 2, 5, 3, 1, 4, 4, 3, 4, 3, 2, 4, 6, 3, 3, 7, 4, 7, 6, 5, 4, 5, 3, 7, 3, 4, 6, 6, 3, 4, 7, 4, 8, 6, 5, 11, 5, 5, 9, 7, 4, 7, 8, 5, 3, 1, 6, 5, 8, 4, 7, 5, 2, 8, 8, 7, 4, 3, 8, 7, 3, 3, 8, 8, 4, 8, 8, 5, 5, 7, 8, 6, 7, 8, 11, 6, 7, 9, 7, 6, 2, 3]

cp's OEIS Frontend

A231577 Number of ways to write n = x + y (x, y > 0) with 2^x + y*(y+1)/2 prime.

Table of values

List of values

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

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

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