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A065446 Decimal expansion of Product_{k>=1} (1-1/2^k)^(-1). 11
3, 4, 6, 2, 7, 4, 6, 6, 1, 9, 4, 5, 5, 0, 6, 3, 6, 1, 1, 5, 3, 7, 9, 5, 7, 3, 4, 2, 9, 2, 4, 4, 3, 1, 1, 6, 4, 5, 4, 0, 7, 5, 7, 9, 0, 2, 9, 0, 4, 4, 3, 8, 3, 9, 1, 3, 2, 9, 3, 5, 3, 0, 3, 1, 7, 5, 8, 9, 1, 5, 4, 3, 9, 7, 4, 0, 4, 2, 0, 6, 4, 5, 6, 8, 7, 9, 2, 7, 7, 4, 0, 2, 9, 4, 8, 4, 3, 3, 5, 3, 5, 0, 8, 8, 0 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,1

REFERENCES

Steven R. Finch, Mathematical Constants, Cambridge, 2003, pp. 354-361.

LINKS

Harry J. Smith, Table of n, a(n) for n=1..2000

Steven R. Finch, Digital Search Tree Constants [Broken link]

Steven R. Finch, Digital Search Tree Constants [From the Wayback machine]

Igor Pak, Greta Panova, Damir Yeliussizov, On the largest Kronecker and Littlewood-Richardson coefficients, arXiv:1804.04693 [math.CO], 2018. [p. 13]

J. Sondow and E. W. Weisstein, MathWorld: Wallis Formula

FORMULA

3.4627466... = Sum_{n>=0} 1/A002884(n)*Product_{j=1..n}2^n/(2^n-1) - Geoffrey Critzer, Jun 30 2017

Equals 1/QPochhammer(1/2, 1/2)_{infinity}. - G. C. Greubel, Jan 18 2018

EXAMPLE

3.46274661945506361153795734292443116454075790290...

MATHEMATICA

N[ Product[ 1/(1 - 1/2^k), {k, 1, Infinity} ], 500 ]

RealDigits[1/QPochhammer[1/2, 1/2], 10, 100][[1]] (* Vaclav Kotesovec, Jun 22 2014 *)

PROG

(PARI) { default(realprecision, 2080); x=prodinf(k=1, 1/(1 - 1/2^k)); for (n=1, 2000, d=floor(x); x=(x-d)*10; write("b065446.txt", n, " ", d)) } \\ Harry J. Smith, Oct 19 2009

CROSSREFS

Cf. A048652, A006099.

Sequence in context: A066977 A007551 A161012 * A159962 A214871 A055173

Adjacent sequences:  A065443 A065444 A065445 * A065447 A065448 A065449

KEYWORD

nonn,cons,changed

AUTHOR

N. J. A. Sloane, Nov 18 2001

EXTENSIONS

More terms from Robert G. Wilson v, Nov 19 2001

Further terms from Vladeta Jovovic, Dec 01 2001

STATUS

approved

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Last modified April 19 06:30 EDT 2019. Contains 322237 sequences. (Running on oeis4.)