# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a212332 Showing 1-1 of 1 %I A212332 #14 Aug 07 2012 10:56:11 %S A212332 1,3,1,5,2,1,3,4,9,1,11,5,3,8,15,2,1,17,10,3,5,9,2,21,1,3,14,11,1,6,5, %T A212332 16,27,3,29,4,8,9,15,20,5,1,35,2,17,4,11,3,39,5,12,41,26,9,3,6,21,28, %U A212332 45,14,1,5,8,3,15,11,4,51,1,9,34,5,17,18,27,10 %N A212332 The difference between the largest and smallest prime factor of n as n runs through the numbers with at least two distinct prime factors. %C A212332 a(n) = A100576(n) if A168638(n) contains only two prime distinct divisors. %C A212332 Nonzero entries of A046665 in the order of appearance. _R. J. Mathar_, Aug 07 2012 %H A212332 Michel Lagneau, Table of n, a(n) for n = 1..10000 %e A212332 a(13) = 3 because A168638(13) = 30 = 2*3*5 and 5-2 = 3. %p A212332 for n from 2 to 200 do %p A212332 gpf := A006530(n) ; %p A212332 spf := A020639(n) ; %p A212332 if gpf <> spf then %p A212332 printf("%d,",gpf-spf) ; %p A212332 end if; %p A212332 end do: # _R. J. Mathar_, Aug 07 2012 %Y A212332 Cf. A100576, A168638. %K A212332 nonn %O A212332 1,2 %A A212332 _Michel Lagneau_, Aug 07 2012 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE