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 A180308 #10 Feb 16 2025 08:33:13 %S A180308 2,8,8,5,7,1,7,1,8,3,4,8,3,9,4,8,5,6,2,5,4,6,8,4,9,2,4,2,8,5,2,3,5,3, %T A180308 4,6,4,1,7,0,4,9,6,7,4,2,3,1,0,3,9,0,0,9,2,5,9,2,6,3,3,2,2,9,7,3,5,8, %U A180308 1,6,3,5,8,2,2,4,6,9,3,3,0,1,1,5,5,4,5,8,9,0,7,0,5,2,7,9,4,9,4,9,0,4,5,1,1 %N A180308 Decimal expansion of the mean length of a line segment picked at random in a 30-60-90 (right) triangle. %H A180308 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/30-60-90Triangle.html">30-60-90 Triangle</a>. %H A180308 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/TriangleLinePicking.html">Triangle Line Picking</a>. %F A180308 Equals (204 + 36*sqrt(3) + 81*log(3) + 2*(9 + 8*sqrt(3))*log(2 + sqrt(3)))/1440. %e A180308 0.28857171834839485625... %t A180308 RealDigits[(204 + 36*Sqrt[3] + 81*Log[3] + 2*(9 + 8*Sqrt[3])*Log[2 + Sqrt[3]])/1440, 10, 120][[1]] (* _Amiram Eldar_, May 25 2023 *) %Y A180308 Cf. A093063, A093064, A180307. %K A180308 nonn,cons %O A180308 0,1 %A A180308 _Eric W. Weisstein_, Aug 25 2010