login
This site is supported by donations to The OEIS Foundation.

 

Logo

Annual Appeal: Please make a donation to keep the OEIS running. In 2018 we replaced the server with a faster one, added 20000 new sequences, and reached 7000 citations (often saying "discovered thanks to the OEIS").
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A004601 Expansion of Pi in base 2 (or, binary expansion of Pi). 63
1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

2,1

COMMENTS

The 10^k-th binary digit of Pi beginning with k=0: 0,0,0,1,1,0,1,1,0, ..., . - Robert G. Wilson v, May 04 2009

It appears to me that, if this is read as a decimal number, it is an example of an irrational number that is not normal (no '2' for example, and if it repeated or terminated, Pi would too). - Alvin H. Belt, Jun 19 2009

REFERENCES

J. P. Delahaye, Le Fascinant Nombre Pi, "100000 digits of pi in base two", pp. 209-210; Pour la Science, Paris 1997.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 2..1000

Francisco Javier Aragón Artacho, 2 billion step walk on the digits of pi

A. Brouty, Les décimales de pi en base 2 jusqu'à 1 million

Elias's Pi Page, Binary representation of pi with 32768 digits

J. Leroy, M. Rigo, and M. Stipulanti, Behavior of Digital Sequences Through Exotic Numeration Systems, Electronic Journal of Combinatorics 24(1) (2017), #P1.44. See w(n) in Example 19.

Steve Pagliarulo, Stu's pi page: base 2 (23 pages) [link was dead, retrieved from the Internet archive]

FORMULA

a(n) = -2*floor(Pi*2^(-4 + n)) + floor(Pi*2^(-3 + n)) for n > 1. - Mariusz Iwaniuk, Apr 28 2017

EXAMPLE

11.0010010000111111011010101000100010000...

MATHEMATICA

RealDigits[Pi, 2, 75][[1]]

PROG

(PARI) binary(Pi) \\ Altug Alkan, Apr 08 2018

CROSSREFS

Cf. A000796, A119017, A068425, A117721, A065987, A051480, A007514.

Pi in base b: this sequence (b=2), A004602 (b=3), A004603 (b=4), A004604 (b=5), A004605 (b=6), A004606 (b=7), A006941 (b=8), A004608 (b=9), A000796 (b=10), A068436 (b=11), A068437 (b=12), A068438 (b=13), A068439 (b=14), A068440 (b=15), A062964 (b=16), A060707 (b=60).

Sequence in context: A133100 A216230 A077606 * A114915 A074711 A004585

Adjacent sequences:  A004598 A004599 A004600 * A004602 A004603 A004604

KEYWORD

nonn,base,cons,easy

AUTHOR

N. J. A. Sloane

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 December 11 13:25 EST 2018. Contains 318049 sequences. (Running on oeis4.)