%I A055197
%S A055197 10,14,16,19,20,21,25,26,27,28,30,31,32,33,34,35,38,39,41,42,43,44,45,
%T A055197 46,47,48,49,50,51,52,54,56,57,58,64,65,66,67,70,71,72,73,75,76,77,78,
%U A055197 79,80,81,82,84,85,87,88,89,90,91,92,94,95,96,98,99,100
%N A055197 A005728(n) is not prime.
%C A055197 From a question posed by Leo Moser.
%D A055197 Martin Gardner, "The Last Recreations," Chapter entitled "Strong Laws 
               of Small Primes," Copernicus, Springer-Verlag, NY 1997, page 199.
%t A055197 s=1; Do[ s=s+EulerPhi[ n ]; If[ !PrimeQ[ s ], Print[ n ] ], {n, 1, 100} 
               ]
%Y A055197 Cf. A005728.
%Y A055197 Sequence in context: A162708 A067188 A092632 this_sequence A116610 A096851 
               A121893
%Y A055197 Adjacent sequences: A055194 A055195 A055196 this_sequence A055198 A055199 
               A055200
%K A055197 easy,nonn
%O A055197 0,1
%A A055197 Robert G. Wilson v (rgwv(AT)rgwv.com), Jul 04 2000