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.

A091377 Numbers having fewer prime factors than the value of their smallest prime factor.

This page as a plain text file.
%I A091377 #15 Dec 28 2024 11:45:10
%S A091377 1,2,3,5,7,9,11,13,15,17,19,21,23,25,29,31,33,35,37,39,41,43,47,49,51,
%T A091377 53,55,57,59,61,65,67,69,71,73,77,79,83,85,87,89,91,93,95,97,101,103,
%U A091377 107,109,111,113,115,119,121,123,125,127,129,131,133,137,139,141,143
%N A091377 Numbers having fewer prime factors than the value of their smallest prime factor.
%C A091377 A091371(a(n)) > 0: A001222(a(n)) < A020639(a(n)).
%H A091377 Charles R Greathouse IV, <a href="/A091377/b091377.txt">Table of n, a(n) for n = 1..10000</a>
%t A091377 Select[Range[143],PrimeOmega[#]<FactorInteger[#][[1,1]]&] (* _James C. McMahon_, Dec 28 2024 *)
%o A091377 (PARI) is(n)=if(n%2==0, return(n==2)); if(n<27, return(1)); forprime(p=2,bigomega(n), if(n%p==0, return(0))); 1 \\ _Charles R Greathouse IV_, Sep 14 2015
%Y A091377 Cf. A091374, A091376, A091375.
%K A091377 nonn,easy
%O A091377 1,2
%A A091377 _Reinhard Zumkeller_, Jan 04 2004