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 A202473 #16 May 26 2025 15:27:26 %S A202473 2,9,7,5,4,7,1,7,1,6,5,8,4,4,0,1,6,2,9,2,7,2,4,2,1,8,5,7,7,7,2,2,5,0, %T A202473 3,1,0,7,9,1,2,3,5,0,2,6,6,0,9,1,3,9,4,6,4,7,9,9,6,8,6,7,3,2,5,1,0,6, %U A202473 6,9,5,8,9,6,8,1,0,6,2,4,0,7,6,6,5,7,4,9,4,3,9,6,6,1,4,3,9,9,6,3,3,5,6,1,8 %N A202473 Decimal expansion of the surface area of a unit Reuleaux triangle. %H A202473 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/ReuleauxTetrahedron.html">Reuleaux Tetrahedron</a> %F A202473 Equals 8*Pi - 18*arccos(1/3). %e A202473 2.9754717165844016292... %t A202473 RealDigits[8*Pi - 18*ArcCos[1/3], 10, 100][[1]] %o A202473 (PARI) 8*Pi - 18*acos(1/3) \\ _Stefano Spezia_, May 26 2025 %Y A202473 Cf. A137914, A228824. %K A202473 nonn,cons %O A202473 1,1 %A A202473 _Eric W. Weisstein_, Dec 19 2011