OFFSET
1,6
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..65537
FORMULA
a(n) = Sum_{d|n} A099104(d). - Antti Karttunen, Jul 02 2018
EXAMPLE
MATHEMATICA
b[n_] := b[n] = If[n == 1, 0, Product[If[n > d^2, 1, 1 - b[d]], {d, Select[Range[n - 1], Mod[n, #] == 0&]}]]; (* b is A099104 *)
a[n_] := Sum[b[d], {d, Divisors[n]}];
Array[a, 105] (* Jean-François Alcover, Dec 06 2021 *)
PROG
(PARI)
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Sep 23 2004
STATUS
approved