OFFSET
1
LINKS
FORMULA
MATHEMATICA
a[n_] := If[!PrimePowerQ[n] && CoprimeQ[n, DivisorSigma[1, n]], 1, 0]; a[1] = 0; Array[a, 100] (* Amiram Eldar, Jul 18 2022 *)
PROG
(PARI) A355816(n) = ((omega(n)>1) && (1==gcd(n, sigma(n))));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jul 18 2022
STATUS
approved