OFFSET
1,2
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..16384
MATHEMATICA
psi[n_] := If[n==1, 1, Times @@ ((#1+1)*#1^(#2-1)& @@@ FactorInteger[n])];
a[n_] := GCD[n+1, psi[n]];
Array[a, 105] (* Jean-François Alcover, Dec 22 2021 *)
PROG
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 29 2021
STATUS
approved