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 A381684 #16 Aug 19 2025 11:24:22 %S A381684 4,6,6,2,2,9,2,8,2,6,4,3,2,9,5,0,6,4,6,0,8,4,8,7,5,5,9,9,0,8,9,8,9,4, %T A381684 9,5,8,1,0,6,2,7,3,3,0,0,4,9,1,0,5,8,1,3,6,4,2,5,9,9,1,8,8,9,3,1,1,5, %U A381684 5,0,8,3,9,7,2,7,1,1,9,5,5,5,2,4,2,4,7,8,7,1 %N A381684 Decimal expansion of the isoperimetric quotient of a truncated tetrahedron. %C A381684 Polya (1954) defines the isoperimetric quotient of a solid as 36*Pi*V^2/S^3, where V and S are the volume and surface area of the solid, respectively. %C A381684 The isoperimetric quotient of a sphere is 1. %D A381684 George Polya, Mathematics and Plausible Reasoning, Vol. 1: Induction and Analogy in Mathematics, Princeton University Press, Princeton, New Jersey, 1954. See pp. 188-189, exercise 43. %H A381684 Paolo Xausa, <a href="/A381684/b381684.txt">Table of n, a(n) for n = 0..10000</a> %H A381684 P. K. Aravind, <a href="https://doi.org/10.4169/college.math.j.42.2.098">How Spherical Are the Archimedean Solids and Their Duals?</a>, The College Mathematics Journal, Vol. 42, Issue 2, 2011, pp. 98-107. %H A381684 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>. %F A381684 Equals 36*Pi*A377275^2/(A377274^3). %F A381684 Equals 529*Pi/(2058*sqrt(3)) = 529*A000796/(2058*A002194). %e A381684 0.4662292826432950646084875599089894958106273300491... %t A381684 First[RealDigits[529*Pi/(2058*Sqrt[3]), 10, 100]] %o A381684 (PARI) 529*Pi/2058/sqrt(3) \\ _Charles R Greathouse IV_, Aug 19 2025 %Y A381684 Cf. A377274 (surface area), A377275 (volume). %Y A381684 Cf. A000796, A002194. %K A381684 nonn,cons,easy %O A381684 0,1 %A A381684 _Paolo Xausa_, Mar 04 2025