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

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A104822 2-digit prime numbers from decimal expansion of Pi. 1
31, 41, 59, 53, 89, 97, 79, 23, 43, 83, 79, 2, 41, 19, 97, 71, 37, 5, 97, 59, 23, 7, 89, 3, 53, 11, 17, 67, 79, 13, 23, 47, 5, 23, 31, 17, 53, 59, 11, 11, 17, 2, 41, 2, 19, 11, 5, 59, 29, 89, 3, 19, 97, 59, 61, 47, 23, 37, 67, 83, 31, 71, 19, 23, 3, 61, 43, 13, 7, 2, 41, 73, 37, 31, 17 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Start with decimal expansion of Pi, 3,1,4,1,5,9,2,6,5,3,5,8,9,7,9,3,2,3,8,4,6,2,6,4,3... Make the sections with two successive digits: s={3,1},{1,4},{4,1},{1,5},{5,9},{9,2},{2,6},{6,5},{5,3},{3,5},{5,8},{8,9},{9,7},{7,9},{9,3},{3,2},{2,3},... Then A104822(n) = prime number from digits of [s(m)]: 31,41,59,53,89,97,79,23,...

Note that leading zeros are allowed, so the sequence of digits ...02...05...07...03... leads to the terms a(12)=2, a(18)=5, a(22)=7, a(24)=3, etc. - M. F. Hasler, Oct 25 2011

LINKS

Table of n, a(n) for n=1..75.

MATHEMATICA

Select[ FromDigits /@ Partition[ RealDigits[Pi, 10, 330][[1]], 2, 1], PrimeQ[ # ] &] (* Robert G. Wilson v, Mar 28 2005 *)

PROG

(PARI) for(i=1, 99, isprime(p=Pi\.1^i%100)&print1(p", "))  \\ M. F. Hasler, Oct 25 2011

CROSSREFS

Sequence in context: A342216 A103490 A105320 * A198175 A238397 A087054

Adjacent sequences:  A104819 A104820 A104821 * A104823 A104824 A104825

KEYWORD

nonn,base

AUTHOR

Zak Seidov, Mar 27 2005

EXTENSIONS

More terms from Robert G. Wilson v, Mar 28 2005

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 May 21 00:36 EDT 2022. Contains 353886 sequences. (Running on oeis4.)