A008784 - cp's OEIS frontend

A008784 Numbers k such that sqrt(-1) mod k exists; or, numbers that are primitively represented by x^2 + y^2.

n	a(n)
1	1
2	2
3	5
4	10
5	13
6	17
7	25
8	26
9	29
10	34
11	37
12	41
13	50
14	53
15	58
16	61
17	65
18	73
19	74
20	82
21	85
22	89
23	97
24	101
25	106
26	109
27	113
28	122
29	125
30	130
31	137
32	145
33	146
34	149
35	157
36	169
37	170
38	173
39	178
40	181
41	185
42	193
43	194
44	197
45	202
46	205
47	218
48	221
49	226
50	229
51	233
52	241
53	250
54	257
55	265
56	269
57	274
58	277
59	281
60	289

[1, 2, 5, 10, 13, 17, 25, 26, 29, 34, 37, 41, 50, 53, 58, 61, 65, 73, 74, 82, 85, 89, 97, 101, 106, 109, 113, 122, 125, 130, 137, 145, 146, 149, 157, 169, 170, 173, 178, 181, 185, 193, 194, 197, 202, 205, 218, 221, 226, 229, 233, 241, 250, 257, 265, 269, 274, 277, 281, 289]

cp's OEIS Frontend

A008784 Numbers k such that sqrt(-1) mod k exists; or, numbers that are primitively represented by x^2 + y^2.

Table of values

List of values

n	a(n)
1	1
2	2
3	5
4	10
5	13
6	17
7	25
8	26
9	29
10	34
11	37
12	41
13	50
14	53
15	58
16	61
17	65
18	73
19	74
20	82
21	85
22	89
23	97
24	101
25	106
26	109
27	113
28	122
29	125
30	130
31	137
32	145
33	146
34	149
35	157
36	169
37	170
38	173
39	178
40	181
41	185
42	193
43	194
44	197
45	202
46	205
47	218
48	221
49	226
50	229
51	233
52	241
53	250
54	257
55	265
56	269
57	274
58	277
59	281
60	289

n	a(n)
1	1
2	2
3	5
4	10
5	13
6	17
7	25
8	26
9	29
10	34
11	37
12	41
13	50
14	53
15	58
16	61
17	65
18	73
19	74
20	82
21	85
22	89
23	97
24	101
25	106
26	109
27	113
28	122
29	125
30	130
31	137
32	145
33	146
34	149
35	157
36	169
37	170
38	173
39	178
40	181
41	185
42	193
43	194
44	197
45	202
46	205
47	218
48	221
49	226
50	229
51	233
52	241
53	250
54	257
55	265
56	269
57	274
58	277
59	281
60	289

n	a(n)
1	1
2	2
3	5
4	10
5	13
6	17
7	25
8	26
9	29
10	34
11	37
12	41
13	50
14	53
15	58
16	61
17	65
18	73
19	74
20	82
21	85
22	89
23	97
24	101
25	106
26	109
27	113
28	122
29	125
30	130
31	137
32	145
33	146
34	149
35	157
36	169
37	170
38	173
39	178
40	181
41	185
42	193
43	194
44	197
45	202
46	205
47	218
48	221
49	226
50	229
51	233
52	241
53	250
54	257
55	265
56	269
57	274
58	277
59	281
60	289