OFFSET
1,2
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
676 = 1010100100 in base 2, phi(676) = 312 = 100111000 in base 2, hence 676 is in the sequence.
MATHEMATICA
Select[Range[500], DigitCount[#, 2, 1]==DigitCount[EulerPhi[#], 2, 1]&] (* Harvey P. Dale, Jun 17 2021 *)
PROG
(PARI) for(n=1, 1000, if(sum(i=1, length(binary(n)), component(binary(n), i))==sum(i=1, length(binary(eulerphi(n))), component(binary(eulerphi(n)), i)), print1(n, ", ")))
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Benoit Cloitre, Jun 01 2002
STATUS
approved