OFFSET
1,2
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
MATHEMATICA
Select[Range[5000], EulerPhi[#*DivisorSigma[1, #]]==EulerPhi[#]^2&] (* Harvey P. Dale, Jan 25 2013 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Benoit Cloitre, May 26 2003
STATUS
approved