OFFSET
1,3
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..12500
FORMULA
MATHEMATICA
Array[#2/GCD[#1, #2] & @@ {If[# < 2, 0, # Total[#2/#1 & @@@ FactorInteger[#]]] &@ Abs[#], EulerPhi[#]} &, 93] (* Michael De Vlieger, Mar 11 2021 *)
PROG
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 11 2021
STATUS
approved