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%I #15 Dec 03 2018 02:47:22
%S 0,0,0,0,1,1,0,1,0,1,0,1,2,0,3,1,3,1,0,3,2,0,0,3,4,4,0,1,2,7,0,1,0,3,
%T 3,2,5,0,6,7,4,4,0,2,4,0,0,5,0,6,7,10,4,1,3,4,0,4,0,10,3,0,3,1,11,3,0,
%U 8,1,5,0,4,6,7,13,0,3,9,0,10,0,6,0
%N Number of pairwise incongruent triangles with integer sides and positive integer area and longest side of length n.
%H Amiram Eldar, <a href="/A054875/b054875.txt">Table of n, a(n) for n = 1..10000</a>
%t okQ[x_, y_, z_] := If[x + y <= z, False, Module[{s = (x + y + z)/2}, IntegerQ[ Sqrt[s(s-x)(s-y)(s-z)]]] ]; a[n_] := Module[{num = 0}, Do[Do[If[okQ[x,y,n], num++], {x,1,y}], {y,1,n}]; num]; Array[a, 100] (* _Amiram Eldar_, Nov 22 2018 *)
%Y Cf. A054876, A055592, A070787, A123323, A239246, A322105.
%K nonn
%O 1,13
%A _Henry Bottomley_, May 26 2000
%E Name and offset changed to align with 2012 changes to A054876 by _Peter Munn_, Nov 23 2018