OFFSET
1,1
COMMENTS
For the third term we have the relation 2592=2^5*9^2. So phi(2592)=phi(2^5*9^2)=phi(2^5)*phi(9^2).
EXAMPLE
39602752 is in the sequence because phi(39602752)=
phi(3^9)*phi(6^0)*phi(2^7)*phi(5^2).
MATHEMATICA
Do[h = IntegerDigits[n]; k = Length[h]; If[EvenQ[k] && Select[ Range[k/2], h[[2#-1]] == 0 &] == {} && EulerPhi[n]== Product[EulerPhi[h[[2j-1]]^h[[2j]]], {j, k/2}], Print[n]], {n, 35000000}]
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Farideh Firoozbakht, Aug 26 2005
STATUS
approved