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A010482
Decimal expansion of square root of 27.
14
5, 1, 9, 6, 1, 5, 2, 4, 2, 2, 7, 0, 6, 6, 3, 1, 8, 8, 0, 5, 8, 2, 3, 3, 9, 0, 2, 4, 5, 1, 7, 6, 1, 7, 1, 0, 0, 8, 2, 8, 4, 1, 5, 7, 6, 1, 4, 3, 1, 1, 4, 1, 8, 8, 4, 1, 6, 7, 4, 2, 0, 9, 3, 8, 3, 5, 5, 7, 9, 9, 0, 5, 0, 7, 2, 6, 4, 0, 0, 1, 1, 1, 2, 4, 3, 4, 3, 8, 5, 6, 0, 2, 7, 1, 7, 4, 5, 7, 2
OFFSET
1,1
COMMENTS
Continued fraction expansion is 5 followed by {5, 10} repeated (A040021). - Harry J. Smith, Jun 04 2009
6 + sqrt(27) represents the surface of a dodecahedron of side equal to one. S = 3*a^2(2 + sqrt(3)) with a = 1. - Vincenzo Librandi, Jul 10 2010
sqrt(27) is the perimeter of an equilateral triangle whose incircle's diameter is 1. - Martin Janecke, May 31 2016
If r = 2*a * sin(3t)/sin(2t) and x*(x^2+y^2) = a * (3x^2-y^2) are respectively a polar equation and a Cartesian equation of the Maclaurin trisectrix, then sqrt(27) * a^2 = area of the loop of this trisectrix = area between the curve and its asymptote (see Mathcurve link). - Bernard Schott, Jul 14 2020
Area of a regular hexagon with side length sqrt(2). - Christoph B. Kassir, Sep 29 2022
The solution of x^sqrt(3)=sqrt(3)^x, see e.g. A360148. - R. J. Mathar, Mar 24 2023
FORMULA
Equals 3*sqrt(3) = 3 * A002194. - Bernard Schott, Jul 14 2020
Equals 2 * A104956. - Christoph B. Kassir, Oct 02 2022
EXAMPLE
5.196152422706631880582339024517617100828415761431141884167420938355799....
MATHEMATICA
RealDigits[N[Sqrt[27], 200]][[1]] (* Vladimir Joseph Stephan Orlovsky, Feb 22 2011 *)
PROG
(PARI) default(realprecision, 20080); x=sqrt(27); for (n=1, 20000, d=floor(x); x=(x-d)*10; write("b010482.txt", n, " ", d)); \\ Harry J. Smith, Jun 04 2009
CROSSREFS
Cf. A040021 (continued fraction), A248254 (Egyptian fraction).
Cf. A104956 (half), A002194 (sqrt(3)).
Sequence in context: A198671 A129343 A342634 * A135856 A097414 A154605
KEYWORD
nonn,cons,easy
STATUS
approved