This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A054876 #19 Jun 19 2019 17:47:46
%S A054876 0,0,0,1,2,0,0,1,0,3,0,2,4,1,4,1,4,0,0,6,1,0,0,3,10,5,0,4,6,6,0,1,1,7,
%T A054876 7,2,5,1,8,10,6,2,0,2,5,0,0,3,0,13,13,14,6,0,7,5,0,8,0,14,9,1,3,1,23,
%U A054876 3,0,13,2,9,0,6,7,9,19,4,1,12,0,14,0,8,0
%N A054876 Number of pairwise incongruent triangles with integer sides and positive integer area and second longest side of length n.
%H A054876 Amiram Eldar, <a href="/A054876/b054876.txt">Table of n, a(n) for n = 1..1000</a>
%e A054876 a(10) is 3 because there are three different integer-sided, integer-area triangles with middle side length 10, namely [9,10,17], [10,10,12], and [10,10,16].
%t A054876 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,n,z], num++], {x,1,n}], {z,n,2n}]; num]; Array[a, 100, 0] (* _Amiram Eldar_, Jun 19 2019 *)
%Y A054876 Cf. A054875.
%K A054876 nonn
%O A054876 1,5
%A A054876 _Henry Bottomley_, May 26 2000
%E A054876 Definition corrected and offset changed by _James R. Buddenhagen_, Jan 16 2012
%E A054876 More terms from _Amiram Eldar_, Jun 19 2019