Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A157484
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
%I A157484
%S A157484 55,89,151,197,233,249,295,307,329,341,343,349,461,489,491,569,571,665,
%T A157484 713,739,775,851,857,859,869,871,949,1013,1015,1061,1097,1111,1149
%N A157484 Numbers n such that n-+1 are divisible by exactly 4 primes, counted with 
               multiplicity.
%C A157484 54=2*3*3*3;56=2*2*2*7,...
%t A157484 q=4;lst={};Do[If[Plus@@Last/@FactorInteger[n-1]==q&&Plus@@Last/@FactorInteger[n+1]==q,
               AppendTo[lst,n]],{n,7!}];lst
%Y A157484 Cf. A124936, A014612, A157483
%Y A157484 Sequence in context: A140377 A065912 A039533 this_sequence A027865 A143205 
               A111192
%Y A157484 Adjacent sequences: A157481 A157482 A157483 this_sequence A157485 A157486 
               A157487
%K A157484 nonn
%O A157484 1,1
%A A157484 Vladimir Orlovsky (4vladimir(AT)gmail.com), Mar 01 2009

    
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 December 15 00:47 EST 2009. Contains 170825 sequences.


AT&T Labs Research