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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.

A384876 Smallest number m such that both m-1 and m+1 are products of at least n (not necessarily distinct) primes.

Table of values

n a(n)
1 3
2 5
3 17
4 55
5 161
6 1457
7 2431
8 13121
9 101249
10 153089
11 2086399
12 7991297
13 65071999
14 72630271
15 2829746177
16 2975006719
17 68278476799
18 75389157377
19 159703334911
20 1570258288639
21 9714181341185
22 91845775327231
23 551785225781249
24 2123044908695551
25 4560483868737535
26 4560483868737535
27 424428773098651649

List of values

[3, 5, 17, 55, 161, 1457, 2431, 13121, 101249, 153089, 2086399, 7991297, 65071999, 72630271, 2829746177, 2975006719, 68278476799, 75389157377, 159703334911, 1570258288639, 9714181341185, 91845775327231, 551785225781249, 2123044908695551, 4560483868737535, 4560483868737535, 424428773098651649]

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

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