A220272 - cp's OEIS frontend

A220272 Number of ways to write n=x^2+y (x>0, y>0) with 2xy-1 prime.

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

[0, 0, 1, 1, 2, 1, 2, 1, 1, 3, 2, 2, 2, 1, 1, 3, 3, 1, 3, 2, 2, 3, 2, 2, 3, 2, 2, 3, 1, 1, 4, 3, 1, 2, 2, 2, 5, 3, 3, 3, 4, 3, 3, 1, 3, 3, 2, 2, 4, 4, 2, 6, 2, 2, 4, 4, 2, 3, 1, 2, 5, 4, 1, 3, 3, 3, 6, 2, 3, 5, 4, 3, 3, 3, 3, 6, 3, 2, 4, 2, 3, 4, 3, 2, 5, 3, 5, 2, 1, 1, 9, 4, 3, 4, 3, 5, 3, 2, 2, 2]

cp's OEIS Frontend

A220272 Number of ways to write n=x^2+y (x>0, y>0) with 2xy-1 prime.

Table of values

List of values

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

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

cp's OEIS Frontend

A220272 Number of ways to write n=x^2+y (x>0, y>0) with 2*x*y-1 prime.

Table of values

List of values

A220272 Number of ways to write n=x^2+y (x>0, y>0) with 2xy-1 prime.

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