A104822 2-digit prime numbers from decimal expansion of Pi.

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

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