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A214395 Decimal expansion of 16/27. 0
5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5, 9, 2, 5 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Betz's constant (or Betz's coefficient): maximum efficiency of a turbine. The constant is unfortunately named; Lanchester discovered it before Betz, and Lanchester cites Froude (though it seems that Lanchester was the first to write it explicitly). Joukowsky (also spelled Zhukovsky) and Munk published discoveries the same year as Betz.

REFERENCES

Albert Betz, "Das Maximum der theoretisch möglichen Ausnutzung des Windes durch Windmotoren", Zeitschrift für das gesamte Turbinenwesen 26 (1920), pp. 307-309.

N. E. Joukowsky (Никола́й Его́рович Жуко́вский), Windmill of the NEJ type (in Russian), Transactions of the Central Institute for Aero-Hydrodynamics of Moscow (1920). Appeared in Collected Papers Vol VI, The Joukowsky Institute for AeroHydrodynamics, Moscow, Russia (1937); VI: 405-409 (in Russian).

F. W. Lanchester, A contribution to the theory of propulsion and the screw propeller, Transactions of the Institution of Naval Architects 57 (1915), pp. 98-116. (See pp. 114-115.)

LINKS

Table of n, a(n) for n=0..81.

Albert Betz, The Maximum of the Theoretically Possible Exploitation of Wind by Means of a Wind Motor, Wind Engineering, Vol 37, Issue 4, 2013 (English translation).

Max M. Munk, Wind driven propeller, NACA Technical Memorandums 201 (1920), pp. 1-12 (German original in: Zeitschrift für Flugtechnik und Motorluftschiffahrt August 15, 1920: 220-223)

Index entries for linear recurrences with constant coefficients, signature (0,0,1).

FORMULA

Equals 16 * A021031. - Felix Fröhlich, Jun 17 2017

EXAMPLE

0.5925925925925925925925925925925925925925925925925925925925925925925...

MATHEMATICA

RealDigits[16/27, 10, 120][[1]] (* or *) PadRight[{}, 120, {5, 9, 2}] (* Harvey P. Dale, Dec 04 2012 *)

PROG

(PARI) 16/27.

CROSSREFS

Cf. A021031, A021112.

Sequence in context: A200009 A303662 A011494 * A030125 A111698 A216755

Adjacent sequences:  A214392 A214393 A214394 * A214396 A214397 A214398

KEYWORD

nonn,easy,cons

AUTHOR

Charles R Greathouse IV, Aug 07 2012

STATUS

approved

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Last modified July 22 20:51 EDT 2019. Contains 325226 sequences. (Running on oeis4.)