OFFSET
1,2
COMMENTS
k*A005117(k) is in the sequence iff k is squarefree and gcd(k,A005117(k)) = 1. - Robert Israel, May 22 2015
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
EXAMPLE
30 is in this sequence because the 5th squarefree is 6 and 5*6 = 30.
MAPLE
k:= 0:
count:= 0:
for m from 1 while count < 100 do
if numtheory:-issqrfree(m) then
k:= k+1;
if numtheory:-issqrfree(k) and igcd(k, m)=1 then
count:= count+1;
A[count]:= k*m;
fi
fi
od:
seq(A[i], i=1..count); # Robert Israel, May 22 2015
PROG
(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
CROSSREFS
KEYWORD
nonn
AUTHOR
Juri-Stepan Gerasimov, May 10 2015
EXTENSIONS
Name corrected by Robert Israel, May 22 2015
STATUS
approved