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 A120011 #24 Aug 04 2025 08:56:22 %S A120011 4,3,3,0,1,2,7,0,1,8,9,2,2,1,9,3,2,3,3,8,1,8,6,1,5,8,5,3,7,6,4,6,8,0, %T A120011 9,1,7,3,5,7,0,1,3,1,3,4,5,2,5,9,5,1,5,7,0,1,3,9,5,1,7,4,4,8,6,2,9,8, %U A120011 3,2,5,4,2,2,7,2,0,0,0,0,9,2,7,0,2,8,6,5,4,6,6,8,9,3,1,2,1,4,3 %N A120011 Decimal expansion of sqrt(3)/4. %C A120011 Area of equilateral triangle of side 1. %C A120011 Quadratic number with denominator 4 and minimal polynomial 16x^2 - 3. - _Charles R Greathouse IV_, Jun 30 2021 %C A120011 With offset 1, surface area of a pentagonal bipyramid (Johnson solid J_13) with unit edges. - _Paolo Xausa_, Aug 04 2025 %H A120011 G. C. Greubel, <a href="/A120011/b120011.txt">Table of n, a(n) for n = 0..10000</a> %H A120011 Wikipedia, <a href="https://en.wikipedia.org/wiki/Pentagonal_bipyramid">Pentagonal bipyramid</a>. %H A120011 <a href="/index/Al#algebraic_02">Index entries for algebraic numbers, degree 2</a> %e A120011 0.43301270189221932338186158537646809173570131345259515701395.... %t A120011 RealDigits[Sqrt[3]/4,10,120][[1]] (* _Harvey P. Dale_, Feb 18 2016 *) %o A120011 (PARI) sqrt(3)/4 \\ _Charles R Greathouse IV_, Jun 26 2013 %Y A120011 Cf. A010527. %Y A120011 Cf. Areas of higher regular polygons: A102771, A104956, A178817, A090488, A256853, A178816, A256854, A178809. %K A120011 nonn,cons,easy %O A120011 0,1 %A A120011 _Eric Desbiaux_, Jul 04 2008