A301891 - cp's OEIS frontend

A301891 Number of ways to write 2n^2 as x^2 + y^2 + z^2 + w^2 with x,y,z,w nonnegative integers such that x + 3y + 5z + 15w is a power of 4.

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

[2, 1, 1, 2, 3, 1, 2, 1, 3, 1, 2, 1, 6, 3, 8, 2, 5, 4, 6, 3, 4, 3, 6, 1, 3, 3, 7, 2, 8, 9, 8, 1, 15, 5, 8, 3, 11, 1, 5, 1, 4, 4, 2, 2, 10, 7, 17, 1, 18, 11, 14, 6, 16, 6, 17, 3, 21, 10, 16, 8, 19, 8, 30, 2, 15, 9, 18, 5, 28, 5, 27, 4, 13, 11, 24, 6, 28, 17, 20, 3]

cp's OEIS Frontend

A301891 Number of ways to write 2n^2 as x^2 + y^2 + z^2 + w^2 with x,y,z,w nonnegative integers such that x + 3y + 5z + 15w is a power of 4.

Table of values

List of values

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

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

cp's OEIS Frontend

A301891 Number of ways to write 2*n^2 as x^2 + y^2 + z^2 + w^2 with x,y,z,w nonnegative integers such that x + 3*y + 5*z + 15*w is a power of 4.

Table of values

List of values

A301891 Number of ways to write 2n^2 as x^2 + y^2 + z^2 + w^2 with x,y,z,w nonnegative integers such that x + 3y + 5z + 15w is a power of 4.

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