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%I #8 Jul 27 2020 15:52:13
%S 0,0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,2,2,3,4,5,5,5,5,6,6,7,7,8,8,8,9,10,
%T 10,10,10,11,12,13,13,14,14,15,15,16,16,16,16,17,18,19,19,19,20,21,22,
%U 23,23,24,24,25,26,26,27,28,28,29,30,31,31,31,31,32,32,33,33,34,34,35
%N Number of numbers m <= n with at least one prime factor greater than 2*spf(m), where spf(m) is the smallest prime factor of m (A020639).
%C a(n)+A081304(n)=n; a(114)=A081304(114)=57;
%C a(n)<=n/2 for n<=114, a(n)>n/2 for n>114.
%H Robert Israel, <a href="/A081305/b081305.txt">Table of n, a(n) for n = 1..10000</a>
%p f:= proc(n) local R; R:= numtheory:-factorset(n); if max(R) > 2*min(R) then 1 else 0 fi end proc:
%p ListTools:-PartialSums(map(f, [$1..100])); # _Robert Israel_, Jul 27 2020
%t pfg[n_]:=Module[{f=Transpose[FactorInteger[n]][[1]]},If[Last[f]> 2*First[ f], 1,0]]; Accumulate[Array[pfg,80]] (* _Harvey P. Dale_, Apr 28 2014 *)
%Y Cf. A069900, A081303.
%K nonn
%O 1,14
%A _Reinhard Zumkeller_, Mar 17 2003
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