OFFSET
1,2
COMMENTS
First differs from A274546 at n = 42.
The asymptotic density of this sequence is 1/2.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
FORMULA
a(n) ~ 2*n.
Sum_{n>=1} 1/a(n)^s = (zeta(s)/zeta(2*s)) / Product_{p in A366640} (1 + 1/p^s), s>1.
MATHEMATICA
seq[max_] := With[{ps = {5, 79, 1831}}, If[max <= Max[ps], Select[Range[max], And @@ CoprimeQ[#, ps] && SquareFreeQ[#] &], Print["Add to ps more terms from A366640"]]]; seq[130]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Amiram Eldar, Oct 15 2023
STATUS
approved