cp's OEIS Frontend

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.

A157939 Numbers n divisible by precprime(sqrt(n)) or nextprime(sqrt(n)) but not both, where precprime=A007917, nextprime=A007918.

Table of values

n a(n)
1 8
2 10
3 12
4 18
5 20
6 21
7 24
8 28
9 30
10 40
11 42
12 45
13 55
14 56
15 63
16 66
17 70
18 84
19 88
20 91
21 98
22 99
23 105
24 110
25 112
26 119
27 130
28 132
29 154
30 156
31 165
32 170
33 182
34 187
35 195
36 204
37 208
38 234
39 238
40 247
41 255
42 260
43 272
44 273
45 286
46 304
47 306
48 340
49 342
50 357
51 368
52 380
53 391
54 399
55 414
56 418
57 456

List of values

[8, 10, 12, 18, 20, 21, 24, 28, 30, 40, 42, 45, 55, 56, 63, 66, 70, 84, 88, 91, 98, 99, 105, 110, 112, 119, 130, 132, 154, 156, 165, 170, 182, 187, 195, 204, 208, 234, 238, 247, 255, 260, 272, 273, 286, 304, 306, 340, 342, 357, 368, 380, 391, 399, 414, 418, 456]

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

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