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%I #11 Aug 26 2018 20:15:17
%S 5,29,37,61,101,173,181,197,269,277,293,349,389,509,541,613,653,661,
%T 677,701,757,773,821,877,941,1069,1093,1109,1117,1181,1237,1301,1373,
%U 1597,1613,1693,1733,1741,1789,1877,1933,1997,2029,2053,2069,2141,2221,2269
%N Primes of the form (4n+1)^2 + (4m+2)^2, m,n >= 0.
%H Robert Israel, <a href="/A087879/b087879.txt">Table of n, a(n) for n = 1..10000</a>
%p N:= 10000:
%p A:= NULL:
%p for x from 1 by 4 while x^2 < N do
%p for y from 2 by 4 while x^2 + y^2 < N do
%p v:= x^2 + y^2;
%p if isprime(v) then A:= A,v fi
%p od od:
%p sort(convert({A},list)); # _Robert Israel_, Aug 26 2018
%o Contribution from _Michael B. Porter_, Dec 10 2009: (Start)
%o (PARI) /* numbers of the form (4x+1)^2 + (4y+2)^2 for x,y >= 0 */
%o /* largest possible x */
%o xm(n)=floor((sqrt(n-4)-1)/4)
%o /* determine if n - (4x+1)^2 is a square, and put the square root into a */
%o isform(n)={local(r,a);r=0;for(x=0,xm(n),if(issquare(n-(4*x+1)^2,a),if(Mod(a,4)==Mod(2,4),r=1)));r}
%o /* skip isform() calculation if possible */
%o isA087879(n) = if(n>4 && Mod(n,2)==Mod(1,2) && isprime(n),isform(n),0) (End)
%K nonn
%O 1,1
%A _Cino Hilliard_, Oct 11 2003
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