login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A334422 Decimal expansion of Pi/128. 2
2, 4, 5, 4, 3, 6, 9, 2, 6, 0, 6, 1, 7, 0, 2, 5, 9, 6, 7, 5, 4, 8, 9, 4, 0, 1, 4, 3, 1, 8, 7, 1, 1, 1, 6, 2, 8, 2, 7, 9, 0, 3, 8, 5, 9, 3, 2, 6, 1, 8, 0, 1, 4, 2, 2, 6, 3, 6, 6, 7, 5, 4, 6, 2, 7, 4, 0, 4, 8, 1, 5, 6, 7, 4, 1, 1, 1, 0, 0, 7, 8, 0, 1, 7, 8, 1, 5, 2, 2, 0, 7, 2, 9, 8, 5, 2, 8, 9, 5, 9 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

-1,1

COMMENTS

Consider 4 circles inscribed in a square. Inscribe a square in each circle. And finally, inscribe 4 circles inside each four small squares. Totally we get 16 small circles. Pi/128 is the ratio of the area of any small circle to the area of the initial square. See the link.

Pi/8 (A019675) is the area ratio for the 16 small circles and the initial square.

Pi/128 is also the surface area of a sphere whose diameter is 1/sqrt(128). (Cf A222066). - Omar E. Pol, May 29 2020

LINKS

Table of n, a(n) for n=-1..98.

Kirill Ustyantsev, Geometric interpretation of Pi/128

Index entries for transcendental numbers

FORMULA

Equals Sum_{k>=1} sin(k)^5*cos(k)^5/k. - Amiram Eldar, Jul 11 2020

EXAMPLE

0.02454369260617025967548940143187111628279038593261801422636675462740481567411...

MATHEMATICA

RealDigits[Pi/128, 10, 100][[1]] (* Amiram Eldar, Apr 30 2020 *)

PROG

(PARI)

default(realprecision, 100);

Pi/128

CROSSREFS

Cf. A000796, A019675, A222066.

Sequence in context: A123545 A123546 A339069 * A317499 A004581 A212790

Adjacent sequences: A334419 A334420 A334421 * A334423 A334424 A334425

KEYWORD

nonn,cons

AUTHOR

Kirill Ustyantsev, Apr 30 2020

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 29 01:35 EST 2022. Contains 358421 sequences. (Running on oeis4.)