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 A188940 #7 Feb 14 2025 01:12:43 %S A188940 2,3,4,4,3,5,5,6,2,9,2,5,3,6,2,5,8,6,9,0,8,3,4,6,6,9,2,4,2,4,0,5,7,2, %T A188940 1,7,2,1,6,4,0,0,9,2,3,5,9,7,8,5,6,6,5,3,0,1,5,8,5,1,9,0,2,6,8,4,0,3, %U A188940 1,2,6,2,2,4,3,5,7,7,9,4,9,2,5,9,9,6,1,4,3,3,3,2,0,6,9,2,3,3,9,0,9,0,6,3,9,3,8,3,4,6,5,0,1,3,5,2,1,9,4,6,5,6,2,8,3,6,9,6,9,9 %N A188940 Decimal expansion of (9-sqrt(65))/4. %C A188940 Decimal expansion of the shape (= length/width = (9-sqrt(65))/4) of the lesser (9/2)-contraction rectangle. %C A188940 See A188738 for an introduction to lesser and greater r-contraction rectangles, their shapes, and partitioning these rectangles into a sets of squares in a manner that matches the continued fractions of their shapes. %e A188940 0.23443556292536258690834669242405721721640... %t A188940 r = 9/2; t = (r - (-4 + r^2)^(1/2))/2; FullSimplify[t] %t A188940 N[t, 130] %t A188940 RealDigits[N[t, 130]][[1]] %t A188940 ContinuedFraction[t, 120] %Y A188940 Cf. A188941, A188738. %K A188940 nonn,cons,easy %O A188940 1,1 %A A188940 _Clark Kimberling_, Apr 14 2011