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%I #7 May 12 2018 10:05:30
%S 0,0,0,0,0,0,1,0,0,0,1,0,0,1,1,0,0,1,1,0,1,1,1,1,1,1,1,1,1,1,2,1,1,1,
%T 2,1,1,2,2,1,2,2,2,1,2,2,2,2,2,2,2,2,2,2,3,2,2,2,3,2,2,3,3,2,3,3,3,2,
%U 3,3,3,3,3,3,3,3,3,3,4,3,3,4,4,3,3,4,4,3,4,4
%N Number of integer triangles with perimeter n which are obtuse and isosceles.
%C a(n)=A070101(n)-A024156(n); a(n)=A059169(n)-A070098(n).
%H R. Zumkeller, <a href="/A070080/a070080.txt">Integer-sided triangles</a>
%e For n=11 there are A005044(11)=4 integer triangles: [1,5,5], [2,4,5], [3,3,5] and [3,4,4]; only one of the two obtuses ([2,4,5] and [3,3,5]) is also isosceles; therefore a(11)=1.
%Y Cf. A070080, A070081, A070082, A059169, A070107, A070108, A070133.
%K nonn
%O 1,31
%A _Reinhard Zumkeller_, May 05 2002
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