OFFSET
1,1
EXAMPLE
n=5989003: sigma(n) = 5994000 and n - phi(n) = 4995
MATHEMATICA
Do[ If[ FromDigits[ Reverse[ IntegerDigits[ DivisorSigma[1, n]]]] == n - EulerPhi[n], Print[n]], {n, 10^8}] (* Robert G. Wilson v, Oct 23 2004 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Labos Elemer, Oct 22 2004
EXTENSIONS
More terms from Robert G. Wilson v, Oct 27 2004
a(19)-a(28) from Donovan Johnson, Jan 14 2011
STATUS
approved