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 A070210 #16 Feb 16 2025 08:32:46 %S A070210 1,2,2,3,2,3,3,2,4,3,4,4,3,2,4,5,3,6,4,6,6,6,4,6,3,4,3,6,4,5,4,3,6,5, %T A070210 7,8,6,4,6,8,7,8,9,3,9,5,6,9,8,10,6,6,6,9,8,4,8,9,7,10,6,10,12,6,12, %U A070210 12,5,3,7,8,10,4,9,10,11,6,12,3,6,9,12,12,7,8 %N A070210 Inradii of integer triangles [A070080(A070209(n)), A070081(A070209(n)), A070082(A070209(n))]. %C A070210 a(n) = A070200(A070209(n)). %H A070210 Mohammad K. Azarian, <a href="http://www.jstor.org/stable/25678790">Solution of problem 125: Circumradius and Inradius</a>, Math Horizons, Vol. 16, No. 2 (Nov. 2008), p. 32. %H A070210 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Incircle.html">Incircle</a>. %H A070210 R. Zumkeller, <a href="/A070080/a070080.txt">Integer-sided triangles</a> %e A070210 A070209(3)=212: [A070080(212), A070081(212), A070082(212)] = [5,12,13], let s = A070083(212)/2 = (5+12+13)/2 = 15 then inradius = sqrt((s-5)*(s-5)*(s-6)/s) = sqrt(10*3*2/15) = sqrt(4) = 2; a(3) = A070200(212) = 2. %Y A070210 Cf. A070149, A070201. %K A070210 nonn %O A070210 1,2 %A A070210 _Reinhard Zumkeller_, May 05 2002