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A179587 Decimal expansion of the volume of square cupola with edge length 1. 15
1, 9, 4, 2, 8, 0, 9, 0, 4, 1, 5, 8, 2, 0, 6, 3, 3, 6, 5, 8, 6, 7, 7, 9, 2, 4, 8, 2, 8, 0, 6, 4, 6, 5, 3, 8, 5, 7, 1, 3, 1, 1, 4, 5, 8, 3, 5, 8, 4, 6, 3, 2, 0, 4, 8, 7, 8, 4, 4, 5, 3, 1, 5, 8, 6, 6, 0, 4, 8, 8, 3, 1, 8, 9, 7, 4, 7, 3, 8, 0, 2, 5, 9, 0, 0, 2, 5, 8, 3, 5, 6, 2, 1, 8, 4, 2, 7, 7, 1, 5, 1, 5, 6, 6, 7 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Square cupola: 12 vertices, 20 edges, and 10 faces.

Also, decimal expansion of 1 + product_{n=1..infinity} (1-1/(4n+2)^2). [Bruno Berselli, Apr 02 2013]

LINKS

Table of n, a(n) for n=1..105.

Wolfram Alpha, Johnson solid 4

FORMULA

Digits of 1+2*sqrt(2)/3.

EXAMPLE

1.942809041582063365867792482806465385713114583584632048784453158660...

MATHEMATICA

RealDigits[N[1+(2*Sqrt[2])/3, 200]]

(* From the second comment: *) RealDigits[N[1 + Product[1 - 1/(4 n + 2)^2, {n, 1, Infinity}], 110]][[1]] (* Bruno Berselli, Apr 02 2013 *)

CROSSREFS

Cf. A001622, A010527, A102208, A179290, A179292, A179294, A179449, A179450, A179451, A179452, A179552, A179553, A019881, A224268.

Sequence in context: A155535 A099879 A126774 * A223709 A050016 A033329

Adjacent sequences:  A179584 A179585 A179586 * A179588 A179589 A179590

KEYWORD

nonn,cons,easy

AUTHOR

Vladimir Joseph Stephan Orlovsky, Jul 19 2010

STATUS

approved

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Last modified August 2 00:27 EDT 2014. Contains 245137 sequences.