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A079886 Values of x+y where p runs through the primes of form 4k+1 and p=x^2+y^2, 0<=x<=y.

%I A079886 #17 Jan 15 2015 09:53:07
%S A079886 3,5,5,7,7,9,9,11,11,13,13,11,13,15,15,17,17,15,19,19,15,17,21,19,17,
%T A079886 23,23,21,19,25,25,25,23,25,25,27,25,21,23,29,29,27,25,29,27,31,31,33,
%U A079886 33,25,31,29,35,35,29,35,31,35,27,31,37,29,35,39,37,39,37,33,39,37,41,33
%N A079886 Values of x+y where p runs through the primes of form 4k+1 and p=x^2+y^2, 0<=x<=y.
%C A079886 Also values of y where p runs through the primes of form 4k+1 and 2*p=x^2+y^2, 0 <x<y. - _Colin Barker_, Jul 07 2014
%H A079886 Robert Israel, <a href="/A079886/b079886.txt">Table of n, a(n) for n = 1..10000</a>
%p A079886 N:= 100: # to get values corresponding to primes <= 4*N+1
%p A079886 P:= select(isprime, [seq(4*i+1,i=0..N)]):
%p A079886 F:= proc(p) local f; f:= GaussInt:-GIfactors(p)[2][1][1]; abs(Re(f))+abs(Im(f)) end proc:
%p A079886 map(F,P); # _Robert Israel_, Jul 07 2014
%t A079886 pp = Select[ Range[200] // Prime, Mod[#, 4] == 1 &]; f[p_] := x + y /. ToRules[ Reduce[0 <= x <= y && p == x^2 + y^2, {x, y}, Integers]]; A079886 = f /@ pp (* _Jean-François Alcover_, Jan 15 2015 *)
%Y A079886 Cf. A002330, A002331, A002313, A002144, A079887.
%K A079886 nonn
%O A079886 1,1
%A A079886 _Benoit Cloitre_, Jan 13 2003