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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.

A242719 Smallest even k such that lpf(k-3) > lpf(k-1) >= prime(n), where lpf=least prime factor (A020639).

Table of values

n a(n)
2 10
3 26
4 50
5 170
6 170
7 362
8 362
9 842
10 842
11 1370
12 1370
13 1850
14 1850
15 2210
16 3722
17 3722
18 3722
19 4892
20 5042
21 7082
22 7922
23 7922
24 7922
25 10610
26 10610
27 10610
28 11450
29 13844
30 16130
31 16130
32 17162
33 19322
34 19322
35 24614
36 24614
37 25592
38 29504
39 29930
40 29930
41 36020
42 36020

List of values

[10, 26, 50, 170, 170, 362, 362, 842, 842, 1370, 1370, 1850, 1850, 2210, 3722, 3722, 3722, 4892, 5042, 7082, 7922, 7922, 7922, 10610, 10610, 10610, 11450, 13844, 16130, 16130, 17162, 19322, 19322, 24614, 24614, 25592, 29504, 29930, 29930, 36020, 36020]

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

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