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 A019702 #17 Jul 08 2025 07:35:04 %S A019702 2,9,9,1,9,9,3,0,0,3,4,1,8,8,5,0,7,0,3,2,9,7,7,5,5,6,0,3,1,2,3,3,3,6, %T A019702 0,8,0,1,8,7,7,8,0,3,8,0,3,5,7,2,4,3,6,3,9,0,2,3,7,5,6,7,5,4,5,7,8,8, %U A019702 7,2,7,6,7,8,9,1,6,2,7,6,1,7,7,4,0,9,8,5,5,4,7,9,4,4,8,7,3,3,9 %N A019702 Decimal expansion of 2*Pi/21. %C A019702 Pi/105 = 0.1 * 2*Pi/21 is the mean area of the triangles that can be formed by breaking a unit-length stick in 3 parts, by uniformly and independently choosing 2 points on it (taking only those cases in which the 3 parts can form a triangle) (Mathai, 1999). - _Amiram Eldar_, Jul 28 2020 %D A019702 A. M. Mathai, An Introduction to Geometrical Probability: Distributional Aspects with Applications, CRC Press, 1999. See example 2.5.3, pp. 269-270. %H A019702 Ivan Panchenko, <a href="/A019702/b019702.txt">Table of n, a(n) for n = 0..1000</a> %H A019702 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a> %e A019702 0.299199300341885070329775560312333608018778038035724... %t A019702 RealDigits[2*Pi/21, 10, 100][[1]] (* _Amiram Eldar_, Jul 28 2020 *) %o A019702 (PARI) 2*Pi/21 \\ _Charles R Greathouse IV_, Oct 01 2022 %Y A019702 Equals twice A019688. %Y A019702 Cf. A000796. %K A019702 nonn,cons %O A019702 0,1 %A A019702 _N. J. A. Sloane_