OFFSET
1,1
COMMENTS
If k = p(1)*p(2)*...p(r) is in the sequence, where p(r) is the largest prime factor, then p(1)*p(2)*...*p(r-1) - p(r) = 1 or 2.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
1023 = 3*11*31 and sqrt(1023) = 31.98437... hence 1023 is in the sequence.
MATHEMATICA
Select[Range[2, 50000], SquareFreeQ[#] && FactorInteger[#][[-1, 1]] == Floor[Sqrt[#]] &] (* Amiram Eldar, Apr 23 2022 *)
PROG
(PARI) for(n=2, 100000, if(issquarefree(n)*component(component(factor(n), 1), omega(n))==floor(sqrt(n)), print1(n, ", ")))
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, Jun 11 2002
STATUS
approved