OFFSET
1,4
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
MATHEMATICA
Array[(#-DivisorSigma[0, #])(#-EulerPhi[#])&, 60] (* Harvey P. Dale, May 18 2012 *)
PROG
(Magma) [(n-NumberOfDivisors(n))*(n-EulerPhi(n)): n in [1..60]]; // Vincenzo Librandi, Aug 31 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, May 06 2004
STATUS
approved