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 A386741 #6 Aug 01 2025 09:21:38 %S A386741 2,9,1,2,9,1,0,4,1,4,5,4,0,2,0,9,1,6,6,0,4,2,8,0,0,9,1,0,0,8,3,3,2,0, %T A386741 3,6,3,8,3,6,1,5,3,0,3,7,7,5,1,0,7,9,4,3,4,4,4,1,5,8,7,4,7,3,9,0,7,1, %U A386741 7,5,7,4,5,2,2,0,4,9,4,7,6,8,5,7,6,3,8,9,7,5 %N A386741 Decimal expansion of the volume of a hebesphenomegacorona with unit edges. %C A386741 The hebesphenomegacorona is Johnson solid J_89. %H A386741 Paolo Xausa, <a href="/A386741/b386741.txt">Table of n, a(n) for n = 1..10000</a> %H A386741 Wikipedia, <a href="https://en.wikipedia.org/wiki/Hebesphenomegacorona">Hebesphenomegacorona</a>. %F A386741 Equals the largest real root of 47330370277129322496*x^20 - 722445512980071186432*x^18 + 3596480447590271287296*x^16 - 8432333285523990773760*x^14 + 8973584611317745975296*x^12 - 3065290664181478981632*x^10 + 366229890219212144640*x^8 - 8337259437908852736*x^6 - 22211277300912896*x^4 + 132615435213216*x^2 + 2693461945329. %e A386741 2.912910414540209166042800910083320363836153037751... %t A386741 First[RealDigits[Root[47330370277129322496*#^20 - 722445512980071186432*#^18 + 3596480447590271287296*#^16 - 8432333285523990773760*#^14 + 8973584611317745975296*#^12 - 3065290664181478981632*#^10 + 366229890219212144640*#^8 - 8337259437908852736*#^6 - 22211277300912896*#^4 + 132615435213216*#^2 + 2693461945329 &, 8], 10, 100]] (* or *) %t A386741 First[RealDigits[PolyhedronData["J89", "Volume"], 10, 100]] %Y A386741 Cf. A386742 (surface area). %Y A386741 Cf. A386739, A386740. %K A386741 nonn,cons,easy %O A386741 1,1 %A A386741 _Paolo Xausa_, Aug 01 2025