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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.

A211275 Number of integer pairs (x,y) such that 0 < x <= y <= n and x*y <= floor(n/2).

Table of values

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

List of values

[0, 1, 1, 2, 2, 3, 3, 5, 5, 6, 6, 8, 8, 9, 9, 11, 11, 13, 13, 15, 15, 16, 16, 19, 19, 20, 20, 22, 22, 24, 24, 27, 27, 28, 28, 31, 31, 32, 32, 35, 35, 37, 37, 39, 39, 40, 40, 44, 44, 46, 46, 48, 48, 50, 50, 53, 53, 54, 54, 58, 58, 59, 59, 62, 62, 64, 64, 66, 66, 68, 68]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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