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%I #16 May 13 2013 01:54:19
%S 5,29,37,61,73,101,181,193,241,269,277,293,349,409,521,541,593,661,
%T 701,929,937,1009,1069,1109,1117,1129,1217,1237,1249,1289,1609,1741,
%U 1753,1789,1801,2029,2053,2161,2221,2269,2357,2389,2521,2557,2609,2633,2741,2753
%N Primes of form a^2+b^2 such that |a|+|b| is prime of the form 4k+3.
%H Charles R Greathouse IV, <a href="/A182288/b182288.txt">Table of n, a(n) for n = 1..10000</a>
%e The prime 29=5^2+2^2 such that 5+2=7 is prime of form 4k+3.
%t nn = 60; t = {}; Do[p1 = a^2 + b^2; p2 = a + b; If[p1 < nn^2 && PrimeQ[p1] && Mod[p2, 4] == 3 && PrimeQ[p2], AppendTo[t, p1]], {a, nn}, {b, a}]; Sort[t] (* _T. D. Noe_, Apr 23 2012 *)
%o (PARI) list(lim)=my(v=List(),t);for(a=1,sqrt(lim),forstep(b=(2-a)%4+1, min(a,sqrt(lim-a^2)),4,if(isprime(a+b)&&isprime(t=a^2+b^2), listput(v,t)))); vecsort(Vec(v)) \\ _Charles R Greathouse IV_, Apr 24 2012
%Y Cf. A099332.
%K nonn
%O 1,1
%A _Thomas Ordowski_, Apr 23 2012
%E Extended by _T. D. Noe_, Apr 23 2012
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