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Primes of the form 2^x+2*x+y+2^y, with x and y integers of any sign.
2

%I #6 Mar 31 2012 12:38:25

%S 2,5,7,11,17,19,41,43,53,61,71,79,113,139,149,179,211,277,283,541,563,

%T 1051,2063,2081,2083,2591,4129,4157,8209,8219,8221,8353,16547,32797,

%U 32801,32933,33827,65579,65581,66089,131113,131143,131231,131627,135209

%N Primes of the form 2^x+2*x+y+2^y, with x and y integers of any sign.

%C Because 2^x and 2^y add to an integer only if x=y=-1, the set of x and y to be considered reduces to the set of x, y >= 0. - R. J. Mathar, Oct 29 2011

%t f[x_,y_]:=2^x+2*x+y+2^y; lst={};Do[Do[p=f[x,y];If[PrimeQ[p],AppendTo[lst,p]],{y,-5!,6!}],{x,-5!,6!}];Take[Union[lst],5! ]

%Y Cf. A162573, A162574

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Jul 06 2009