OFFSET
1
COMMENTS
Parity of A017666(n), the denominator of sigma(n)/n (the abundancy index of n).
LINKS
FORMULA
MATHEMATICA
a[n_] := Mod[Denominator[DivisorSigma[-1, n]], 2]; Array[a, 100] (* Amiram Eldar, Mar 03 2023 *)
PROG
(PARI) A361023(n) = (valuation(sigma(n), 2)>=valuation(n, 2));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 03 2023
STATUS
approved