OFFSET
1,2
LINKS
Harry J. Smith, Table of n, a(n) for n = 1..1000
EXAMPLE
5^2 - phi(5)^2 = 25 - 16 = 3^2, so 5 is a term of the sequence.
MATHEMATICA
Select[ Range[ 1, 10^4 ], IntegerQ[ Sqrt[ #^2 - EulerPhi[ # ]^2 ] ] & ]
PROG
(PARI) { n=0; for (m=1, 10^10, if (issquare(m^2 - eulerphi(m)^2), write("b066782.txt", n++, " ", m); if (n==1000, return)) ) } \\ Harry J. Smith, Mar 25 2010
CROSSREFS
KEYWORD
nonn
AUTHOR
Joseph L. Pe, Jan 18 2002
STATUS
approved