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Nonnegative nonprimes which are neither the sum nor the product of two distinct primes.
1

%I #11 May 19 2019 20:37:58

%S 0,1,4,27,117,121,125,135,147,171,189,207,245,255,261,275,289,297,325,

%T 343,345,357,363,387,405,425,429,455,475,477,483,495,507,513,529,531,

%U 539,555,561,567,575,585,605,625,627,637,639,651,657,665,705,715,725,747,765,777

%N Nonnegative nonprimes which are neither the sum nor the product of two distinct primes.

%t prs=Prime[Range[150]];

%t prodprs=Times@@@Subsets[prs,{2}];

%t sumprs=Plus@@@Subsets[prs,{2}];

%t Complement[Range[0,800],prs,prodprs,sumprs] (* _Harvey P. Dale_, Jan 23 2011 *)

%Y Cf. A000040, A166081, A109934, A141468, A006881.

%K nonn

%O 1,3

%A _Juri-Stepan Gerasimov_, Dec 09 2009

%E Definition clarified, sequence corrected (51 removed, 289 inserted) and extended by _R. J. Mathar_, Apr 24 2010