%I A070093
%S A070093 0,0,1,0,1,1,1,1,2,2,2,2,3,2,4,3,5,4,5,5,5,6,6,6,7,7,9,8,10,9,10,10,11,
%T A070093 12,12,12,14,13,16,14,17,16,17,18,18,20,20,20,22,22,24,23,25,26,26,27,
%U A070093 28,30,30,29,32,31,35,33,36,36,38,39,40,40
%N A070093 Number of acute integer triangles with perimeter n.
%C A070093 An integer triangle [A070080(k)<=A070081(k)<=A070082(k)] is acute iff 
               A070085(k)>0;
%C A070093 a(n) = A005044(n) - A070101(n) - A024155(n);
%C A070093 a(n) = A042154(n) + A070098(n).
%H A070093 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               AcuteTriangle.html">Acute Triangle</a>.
%H A070093 R. Zumkeller, <a href="a070080.txt">Integer-sided triangles</a>
%e A070093 For n=9 there are A005044(9)=3 integer triangles: [1,4,4], [2,3,4] and 
               [3,3,3]; two of them are acute, as 2^2+3^2<16=4^2, therefore a(9)=2.
%Y A070093 Cf. A070094, A070095, A070118.
%Y A070093 Sequence in context: A088019 A126759 A029348 this_sequence A058744 A152724 
               A081743
%Y A070093 Adjacent sequences: A070090 A070091 A070092 this_sequence A070094 A070095 
               A070096
%K A070093 nonn
%O A070093 1,9
%A A070093 Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), May 05 2002