OFFSET
1,2
LINKS
Harry J. Smith, Table of n, a(n) for n = 1..1000
MATHEMATICA
Select[Range[4500], Divisible[# EulerPhi[#], DivisorSigma[1, #]]&] (* Harvey P. Dale, Mar 19 2011 *)
PROG
(PARI) { n=0; for (m=1, 10^10, if ((m*eulerphi(m)) % sigma(m) == 0 , write("b066995.txt", n++, " ", m); if (n==1000, return)) ) } \\ Harry J. Smith, Apr 24 2010
(PARI) isok(n) = frac(n*eulerphi(n)/sigma(n)) == 0; \\ Michel Marcus, Jan 31 2018
(GAP) Filtered([1..10^5], n -> n*Phi(n) mod Sigma(n) = 0); # Muniru A Asiru, Jan 31 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Jan 27 2002
STATUS
approved