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A381711 a(n) = A379597(n) - A381710(n).

%I A381711 #5 Mar 15 2025 18:14:35
%S A381711 1,3,7,13,25,41,65,93,133,177,245,305,397,489,609,725,893,1029,1241,
%T A381711 1425,1665,1889,2209,2457,2821,3145,3549,3913,4429,4805,5397,5885,
%U A381711 6493,7045,7781,8341,9185,9881,10745,11489,12545,13297,14453,15385,16497,17517,18917
%N A381711 a(n) = A379597(n) - A381710(n).
%C A381711 a(n) is odd.
%H A381711 Felix Huber, <a href="/A381711/b381711.txt">Table of n, a(n) for n = 1..4051</a>
%H A381711 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/QuadraticEquation.html">Quadratic Equation</a>
%F A381711 a(n) = A379597(n) - A381710(n).
%p A381711 A381711:=proc(n)
%p A381711    option remember;
%p A381711    local a,u,v,w;
%p A381711    if n=1 then
%p A381711       1
%p A381711    else
%p A381711       a:=0;
%p A381711       for u to n-1 do
%p A381711          for v from 0 to n-u do
%p A381711             w:=n-u-v;
%p A381711             if igcd(u,v,w)=1 and v<>0 then
%p A381711                if w=0 or w=v^2/(4*u) then
%p A381711                   a:=a+2
%p A381711                elif w<v^2/(4*u) then
%p A381711                   a:=a+4
%p A381711                fi
%p A381711             fi
%p A381711          od
%p A381711       od;
%p A381711       a+procname(n-1)
%p A381711    fi;
%p A381711 end proc;
%p A381711 seq(A381711(n),n=1..47);
%Y A381711 Cf. A067274, A091626, A091627, A364384, A364385, A365876, A365877, A379597, A381710.
%K A381711 nonn
%O A381711 1,2
%A A381711 _Felix Huber_, Mar 08 2025