Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A069549
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A069549 Smallest composite k such that phi(k) > k*(1-1/n). +0
3
4, 4, 9, 25, 25, 49, 49, 121, 121, 121, 121, 169, 169, 289, 289, 289, 289, 361, 361, 529, 529, 529, 529, 841, 841, 841, 841, 841, 841, 961, 961, 1369, 1369, 1369, 1369, 1369, 1369, 1681, 1681, 1681, 1681, 1849, 1849, 2209, 2209, 2209, 2209, 2809, 2809, 2809 (list; graph; listen)
OFFSET

1,1

COMMENT

Or, least composite k such that k is coprime to the n-1 numbers k+1 ... k+n-1. E.g. a(4) = 25 because 25 is coprime to 26, 27 and 28. - Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Apr 20 2004

FORMULA

a(n)=nextprime(n)^2=A007918(n)^2

CROSSREFS

Cf. A052349.

Sequence in context: A067553 A112683 A117879 this_sequence A118069 A089539 A117416

Adjacent sequences: A069546 A069547 A069548 this_sequence A069550 A069551 A069552

KEYWORD

easy,nonn

AUTHOR

Benoit Cloitre (benoit7848c(AT)orange.fr), Apr 21 2002

EXTENSIONS

Edited by David Wasserman (wasserma(AT)spawar.navy.mil), Apr 23 2007

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified November 29 12:46 EST 2009. Contains 167659 sequences.


AT&T Labs Research