login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A020498 a(n) is the least number > a(n-1) such that a(1) through a(n) do not contain all residues modulo any prime. 4

%I #20 May 17 2016 12:00:09

%S 1,3,7,9,13,19,21,27,31,33,37,43,49,51,57,63,69,73,79,87,91,97,99,103,

%T 111,117,121,129,133,139,141,147,153,157,159,163,169,177,183,187,189,

%U 199,201,211,213,217,231,241,243,247,253,261,267,271,273,279,283,289

%N a(n) is the least number > a(n-1) such that a(1) through a(n) do not contain all residues modulo any prime.

%C Conjecturally, a(n) is the smallest number such that n primes occur infinitely often among (x+a(1), ...,x+a(n)).

%D R. K. Guy's "Unsolved Problems in Number Theory" (2nd edition, Springer, 1994), Section A9.

%H David W. Wilson, <a href="/A020498/b020498.txt">Table of n, a(n) for n = 1..10000</a>

%Y Cf. A020497, A008407.

%K nonn

%O 1,2

%A _Robert G. Wilson v_ and _Christopher E. Thompson_

%E More terms from _David Wasserman_, Aug 17 2005

%E Old name has been interchanged with Wasserman's comment, as old name only a conjectural definition of the sequence. Edited by _Christopher J. Smyth_, May 12 2016

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 29 09:44 EDT 2024. Contains 371268 sequences. (Running on oeis4.)