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.

A080611 a(n) is the smallest number m >= 2 for which the set of prime factors of m, m-1 and m+1 contains at least the first n primes.

Table of values

n a(n)
1 2
2 2
3 4
4 6
5 21
6 155
7 441
8 2925
9 10165
10 342056
11 2781505
12 10631544
13 163886800
14 498936010
15 5163068911
16 794010643700
17 17635639237580
18 353823355745574
19 16828233620277430
20 224220167903546529
21 11990471619719586785
22 113367767003198032480
23 4446177962278202834685
24 118332081735203144063619
25 1103720538399012083835935
26 78239926422758111576984420

List of values

[2, 2, 4, 6, 21, 155, 441, 2925, 10165, 342056, 2781505, 10631544, 163886800, 498936010, 5163068911, 794010643700, 17635639237580, 353823355745574, 16828233620277430, 224220167903546529, 11990471619719586785, 113367767003198032480, 4446177962278202834685, 118332081735203144063619, 1103720538399012083835935, 78239926422758111576984420]

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

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