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 A070145 #11 Feb 16 2025 08:32:46 %S A070145 39,52,269,372,375,862,957,972,1204,1955,1971,1988,2790,2796,3818, %T A070145 5374,6522,6880,6881,6921,7234,7310,7341,7360,9198,9207,10272,14506, %U A070145 15101,15177,15237,21289,21493,21540,21552,21589 %N A070145 Numbers n such that [A070080(n), A070081(n), A070082(n)] is an isosceles integer triangle with integer area. %H A070145 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/HeronianTriangle.html">Heronian Triangle</a>. %H A070145 R. Zumkeller, <a href="/A070080/a070080.txt">Integer-sided triangles</a> %e A070145 a(1)=39: [A070080(39), A070081(39), A070082(39)] = [5=5<6], area^2 = s*(s-5)*(s-5)*(s-6) with s=A070083(39)/2=(5+5+6)/2=8, area^2=8*3*3*2=16*9 is an integer square, therefore A070086(39)=area=4*3=12. %Y A070145 Cf. A070142, A070144, A070139. %K A070145 nonn %O A070145 1,1 %A A070145 _Reinhard Zumkeller_, May 05 2002