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%I #14 Mar 06 2017 19:34:01
%S 8,13,18,20,25,29,32,34,40,41,45,50,52,53,58,61,65,68,72,73,74,80,85,
%T 89,90,97,98,100,104,106,109,113,116,117,125,128,130,136,137,145,146,
%U 148,149,153,157,160,162,164,169,170,173,178,180,181,185,193,194,200
%N Numbers that can be expressed as a sum of two squares, each >=2.
%H Robert Israel, <a href="/A085989/b085989.txt">Table of n, a(n) for n = 1..10000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Landau-RamanujanConstant.html">Landau-Ramanujan Constant</a>
%e 8 = 2^2 + 2^2, 13 = 2^2 + 3^2, ...
%p filter:= n -> ormap(t -> subs(t,x)>1 and subs(t,y) > 1, [isolve(x^2 + y^2 = n)]):
%p select(filter, [$0..200]); # _Robert Israel_, Mar 06 2017
%t r[n_] := Reduce[2 <= x <= y && n == x^2 + y^2, {x, y}, Integers]; Select[Range[200], r[#] =!= False &] (* _Jean-François Alcover_, Oct 29 2012 *)
%Y Cf. A001481.
%K nonn
%O 1,1
%A _Eric W. Weisstein_, Jul 06 2003
%E Offset changed by _Robert Israel_, Mar 06 2017
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