login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A078585 Decimal expansion of Sum_{n>=0} 1/4^(2^n). 11
3, 1, 6, 4, 2, 1, 5, 0, 9, 0, 2, 1, 8, 9, 3, 1, 4, 3, 7, 0, 8, 0, 7, 9, 7, 3, 7, 5, 3, 0, 5, 2, 5, 2, 2, 1, 7, 0, 3, 3, 1, 1, 3, 7, 5, 9, 2, 0, 5, 5, 2, 8, 0, 4, 3, 4, 1, 2, 1, 0, 9, 0, 3, 8, 4, 3, 0, 5, 5, 6, 1, 4, 1, 9, 4, 5, 5, 5, 3, 0, 0, 0, 6, 0, 4, 8, 5, 3, 1, 3, 2, 4, 8, 3, 9, 7, 2, 6, 5, 6, 1, 7, 5, 5, 8 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Harry J. Smith, Table of n, a(n) for n = 0..20000

Aubrey J. Kempner, On Transcendental Numbers, Transactions of the American Mathematical Society, volume 17, number 4, October 1916, pages 476-482.

Index entries for transcendental numbers

FORMULA

Equals -Sum_{k>=1} mu(2*k)/(4^k - 1), where mu is the Möbius function (A008683). - Amiram Eldar, Jul 12 2020

Equals A007404 - 1/2. - Kevin Ryde, Nov 11 2020

EXAMPLE

0.316421509021893143708079737530525221703311375920552804341210903843055...

MATHEMATICA

RealDigits[ N[ Sum[1/4^(2^n), {n, 0, Infinity}], 110]][[1]]

PROG

(PARI) { default(realprecision, 20080); x=suminf(n=0, 1/4^(2^n)); x*=10; for (n=0, 20000, d=floor(x); x=(x-d)*10; write("b078585.txt", n, " ", d)); } \\ Harry J. Smith, May 11 2009

CROSSREFS

Continued fraction is given in A006464.

Similar sums: A007404, A078885, A078886, A078887, A078888, A078889, A078890, A036987.

Sequence in context: A207615 A209165 A121437 * A116551 A213783 A163330

Adjacent sequences:  A078582 A078583 A078584 * A078586 A078587 A078588

KEYWORD

cons,nonn

AUTHOR

Robert G. Wilson v, Dec 01 2002

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 2 17:20 EST 2021. Contains 341754 sequences. (Running on oeis4.)