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%I #24 Nov 13 2016 16:00:46
%S 1,30,42,70,165,247,330,442,570,805,1247,1457,1749,1870,1995,2183,
%T 2318,2418,2706,2814,2967,3358,3478,4182,4505,4785,5187,5394,5546,
%U 5917,6262,7169,7590,7770,8023,8395,9471,9906,10191,10906,11122,11730,11954,12727,13286,14043,15326,16665,17201
%N Squarefree numbers that are k*A005117(k) for some k.
%C k*A005117(k) is in the sequence iff k is squarefree and gcd(k,A005117(k)) = 1. - _Robert Israel_, May 22 2015
%H Charles R Greathouse IV, <a href="/A257832/b257832.txt">Table of n, a(n) for n = 1..10000</a>
%F A005117(m) equal to k*A005117(k).
%e 30 is in this sequence because the 5th squarefree is 6 and 5*6 = 30.
%p k:= 0:
%p count:= 0:
%p for m from 1 while count < 100 do
%p if numtheory:-issqrfree(m) then
%p k:= k+1;
%p if numtheory:-issqrfree(k) and igcd(k,m)=1 then
%p count:= count+1;
%p A[count]:= k*m;
%p fi
%p fi
%p od:
%p seq(A[i],i=1..count); # _Robert Israel_, May 22 2015
%o (PARI) list(lim)=my(v=List(),k,t); for(s=1,lim,if(issquarefree(s), t=k++*s; if(t>lim, return(Vec(v))); if(issquarefree(t), listput(v,t)))) \\ _Charles R Greathouse IV_, May 22 2015
%Y Cf. A005117.
%K nonn
%O 1,2
%A _Juri-Stepan Gerasimov_, May 10 2015
%E Name corrected by _Robert Israel_, May 22 2015
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