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 A180014 #18 Oct 01 2022 00:41:21 %S A180014 5,9,9,9,9,0,8,0,7,4,3,2,1,6,3,3,3,0,5,5,7,8,8,8,8,7,6,6,5,8,4,0,3,4, %T A180014 6,3,2,8,1,2,4,9,7,5,2,7,6,4,5,2,8,7,6,0,7,3,3,7,7,8,1,8,7,6,8,2,8,2, %U A180014 6,8,3,4,5,5,9,8,5,9,6,9,7,6,9,4,9,9,0,5,1,5,1,6,5,1,4,5,9,9,0,9,3,2,8,4,3,2,4,0,6 %N A180014 Decimal expansion of Pi/(2*phi^2). %C A180014 This is the first of the three angles (in radians) of a unique triangle that is right angled and where the angles are in a Geometric Progression - pi/(2*phi^2), pi/(2*phi), pi/2. The angles (in degrees) are approx 34.377, 55.623, 90. %H A180014 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a> %F A180014 pi/(2*phi^2) = A019669 / A104457 = (3 - sqrt(5)) * Pi/4. %e A180014 0.5999908074321633305578888766584034632812497527645287607337781876828268345598596... %t A180014 RealDigits[N[Pi/(2(GoldenRatio)^2),100]][[1]] %o A180014 (PARI) Pi/4*(3-sqrt(5)) \\ _Charles R Greathouse IV_, Jul 29 2011 %K A180014 easy,nonn,cons %O A180014 0,1 %A A180014 _Frank M Jackson_, Aug 06 2010 %E A180014 Partially edited by R. J. Mathar, Aug 07 2010 %E A180014 Mathematica program edited by _Harvey P. Dale_, Jul 10 2012