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 A232808 Decimal expansion of the surface area of a 3D sphere with unit volume. 10
 4, 8, 3, 5, 9, 7, 5, 8, 6, 2, 0, 4, 9, 4, 0, 8, 9, 2, 2, 1, 5, 0, 9, 0, 0, 5, 3, 9, 9, 1, 7, 8, 5, 4, 8, 1, 6, 8, 3, 3, 8, 4, 2, 2, 1, 6, 9, 7, 1, 5, 8, 4, 6, 6, 7, 0, 7, 6, 8, 7, 6, 2, 2, 6, 1, 3, 6, 8, 5, 2, 8, 9, 5, 1, 7, 1, 4, 3, 5, 8, 2, 2, 7, 3, 8, 4, 6 (list; constant; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS More generally, the ratio (surface)/(volume)^(2/3), characteristic of the shape of a bounded 3D body, which is invariant under linear scaling and known as the surface index. Its common value for all spheres is the smallest possible among all closed 3D bodies (for a cube, for example, it is exactly 6.0). LINKS Stanislav Sykora, Table of n, a(n) for n = 1..2000 FORMULA (36*Pi)^(1/3) = 6*A019673^(1/3). EXAMPLE 4.83597586204940892215090053991785481683384221697158466707687622613685... MATHEMATICA RealDigits[(36 Pi)^(1/3), 10, 90][[1]] (* Bruno Berselli, Dec 01 2013 *) CROSSREFS Cf. A000796 (Pi), A019673 (Pi/6); other sphere metrics: A019694, A019699, A087198, A087199. Sequence in context: A204993 A234001 A248946 * A248508 A065191 A229988 Adjacent sequences:  A232805 A232806 A232807 * A232809 A232810 A232811 KEYWORD nonn,cons,easy AUTHOR Stanislav Sykora, Nov 30 2013 STATUS approved

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Last modified December 19 08:25 EST 2018. Contains 318245 sequences. (Running on oeis4.)