OFFSET
1,1
COMMENTS
Note that for all primes p > 3, phi(3p) = phi(p) + phi(2p).
MATHEMATICA
lst={}; Do[p=Prime[n]; k=1; While[EulerPhi[p+k]!=EulerPhi[p]+EulerPhi[k], k++ ]; If[k==2p, AppendTo[lst, p]], {n, 3, 200}]; lst
CROSSREFS
KEYWORD
nonn
AUTHOR
T. D. Noe, Jan 19 2004
STATUS
approved