A002654 - cp's OEIS frontend

A002654 Number of ways of writing n as a sum of at most two nonzero squares, where order matters; also (number of divisors of n of form 4m+1) - (number of divisors of form 4m+3).

n	a(n)
1	1
2	1
3	0
4	1
5	2
6	0
7	0
8	1
9	1
10	2
11	0
12	0
13	2
14	0
15	0
16	1
17	2
18	1
19	0
20	2
21	0
22	0
23	0
24	0
25	3
26	2
27	0
28	0
29	2
30	0
31	0
32	1
33	0
34	2
35	0
36	1
37	2
38	0
39	0
40	2
41	2
42	0
43	0
44	0
45	2
46	0
47	0
48	0
49	1
50	3
51	0
52	2
53	2
54	0
55	0
56	0
57	0
58	2
59	0
60	0
61	2
62	0
63	0
64	1
65	4
66	0
67	0
68	2
69	0
70	0
71	0
72	1
73	2
74	2
75	0
76	0
77	0
78	0
79	0
80	2
81	1
82	2
83	0
84	0
85	4
86	0
87	0
88	0
89	2
90	2
91	0
92	0
93	0
94	0
95	0
96	0
97	2
98	1
99	0
100	3
101	2
102	0
103	0
104	2
105	0

[1, 1, 0, 1, 2, 0, 0, 1, 1, 2, 0, 0, 2, 0, 0, 1, 2, 1, 0, 2, 0, 0, 0, 0, 3, 2, 0, 0, 2, 0, 0, 1, 0, 2, 0, 1, 2, 0, 0, 2, 2, 0, 0, 0, 2, 0, 0, 0, 1, 3, 0, 2, 2, 0, 0, 0, 0, 2, 0, 0, 2, 0, 0, 1, 4, 0, 0, 2, 0, 0, 0, 1, 2, 2, 0, 0, 0, 0, 0, 2, 1, 2, 0, 0, 4, 0, 0, 0, 2, 2, 0, 0, 0, 0, 0, 0, 2, 1, 0, 3, 2, 0, 0, 2, 0]

cp's OEIS Frontend

A002654 Number of ways of writing n as a sum of at most two nonzero squares, where order matters; also (number of divisors of n of form 4m+1) - (number of divisors of form 4m+3).

Table of values

List of values

n	a(n)
1	1
2	1
3	0
4	1
5	2
6	0
7	0
8	1
9	1
10	2
11	0
12	0
13	2
14	0
15	0
16	1
17	2
18	1
19	0
20	2
21	0
22	0
23	0
24	0
25	3
26	2
27	0
28	0
29	2
30	0
31	0
32	1
33	0
34	2
35	0
36	1
37	2
38	0
39	0
40	2
41	2
42	0
43	0
44	0
45	2
46	0
47	0
48	0
49	1
50	3
51	0
52	2
53	2
54	0
55	0
56	0
57	0
58	2
59	0
60	0
61	2
62	0
63	0
64	1
65	4
66	0
67	0
68	2
69	0
70	0
71	0
72	1
73	2
74	2
75	0
76	0
77	0
78	0
79	0
80	2
81	1
82	2
83	0
84	0
85	4
86	0
87	0
88	0
89	2
90	2
91	0
92	0
93	0
94	0
95	0
96	0
97	2
98	1
99	0
100	3
101	2
102	0
103	0
104	2
105	0

n	a(n)
1	1
2	1
3	0
4	1
5	2
6	0
7	0
8	1
9	1
10	2
11	0
12	0
13	2
14	0
15	0
16	1
17	2
18	1
19	0
20	2
21	0
22	0
23	0
24	0
25	3
26	2
27	0
28	0
29	2
30	0
31	0
32	1
33	0
34	2
35	0
36	1
37	2
38	0
39	0
40	2
41	2
42	0
43	0
44	0
45	2
46	0
47	0
48	0
49	1
50	3
51	0
52	2
53	2
54	0
55	0
56	0
57	0
58	2
59	0
60	0
61	2
62	0
63	0
64	1
65	4
66	0
67	0
68	2
69	0
70	0
71	0
72	1
73	2
74	2
75	0
76	0
77	0
78	0
79	0
80	2
81	1
82	2
83	0
84	0
85	4
86	0
87	0
88	0
89	2
90	2
91	0
92	0
93	0
94	0
95	0
96	0
97	2
98	1
99	0
100	3
101	2
102	0
103	0
104	2
105	0

n	a(n)
1	1
2	1
3	0
4	1
5	2
6	0
7	0
8	1
9	1
10	2
11	0
12	0
13	2
14	0
15	0
16	1
17	2
18	1
19	0
20	2
21	0
22	0
23	0
24	0
25	3
26	2
27	0
28	0
29	2
30	0
31	0
32	1
33	0
34	2
35	0
36	1
37	2
38	0
39	0
40	2
41	2
42	0
43	0
44	0
45	2
46	0
47	0
48	0
49	1
50	3
51	0
52	2
53	2
54	0
55	0
56	0
57	0
58	2
59	0
60	0
61	2
62	0
63	0
64	1
65	4
66	0
67	0
68	2
69	0
70	0
71	0
72	1
73	2
74	2
75	0
76	0
77	0
78	0
79	0
80	2
81	1
82	2
83	0
84	0
85	4
86	0
87	0
88	0
89	2
90	2
91	0
92	0
93	0
94	0
95	0
96	0
97	2
98	1
99	0
100	3
101	2
102	0
103	0
104	2
105	0