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%I #13 Dec 28 2015 15:25:38
%S 1,2,3,5,7,8,9,11,13,17,19,23,25,29,31,32,37,41,43,47,49,53,59,61,67,
%T 71,73,79,83,89,97,101,103,107,109,113,121,125,127,128,131,137,139,
%U 149,151,157,163,167,169,173,179,181,191,193,197,199,211,223,227,229,233,239
%N Numbers of the form (noncomposite number)^(noncomposite number), but not p^p where p is prime.
%C The union of {1}, the primes A000040, and powers of the form p^q where p and q are distinct primes.
%Y Cf. A000961, A005117, A008578, A051674.
%K nonn
%O 1,2
%A _Juri-Stepan Gerasimov_, Dec 05 2009
%E Attribute "power-free" removed from the definition by _R. J. Mathar_, Dec 09 2009
%E Inserted a(19)=43 by _Gionata Neri_, Dec 28 2015