OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..241 (terms below 10^12)
EXAMPLE
psi(935) = 36^2.
MATHEMATICA
psi[n_] := If[n < 1, 0, n*Sum[MoebiusMu[d]^2/d, {d, Divisors@n}]]; s = Import["b006972.txt", "Data"][[All, -1]]; Select[s, IntegerQ@Sqrt[psi@#] &]
CROSSREFS
KEYWORD
nonn
AUTHOR
Amiram Eldar, Sep 19 2017
STATUS
approved