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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A261904 Largest x such that n can be written as n = x^2 + y^2 + z^2 with x >= y >= z >= 0, or -1 if no such x exists.

Table of values

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

List of values

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

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