A119017 Primes from binary expansion of Pi, another version. Starting with the first bit of the binary expansion, A004601 = 1,1,0,0,1,0,0,1,0,0,0,0,1,1,1,1,1,1,0,1,1,0,1,... we move rightward until we encounter another 1. Since 11 (= 3 in decimal) is prime, we move to the next 1 and repeat the process.

3, 73, 4639, 67, 3, 3, 3, 3, 3, 5, 3, 5, 5, 5, 17, 17, 1069, 5, 3, 5, 17, 3, 9099300883537, 17, 3, 5, 19, 3, 17, 19, 3, 17, 3, 19, 3, 17, 5, 17, 5, 3, 3, 257, 3, 5, 3, 3, 131, 3, 3, 19, 3, 5, 17, 37, 5, 1153, 1033, 73, 19, 3, 3, 16657, 17, 17, 5, 19, 3, 19, 3, 3, 3, 3, 19, 3, 17, 3, 3

Offset

1,1

Comments

Records: 3, 73, 4649, 9099300883537, 37848784972821936516494858855515680431107854546647118951099098009925403829863969526043052181881, ..., . - Robert G. Wilson v, Jul 24 2006

Links

Table of n, a(n) for n=1..77.

Example

11 = 3
1001001 = 73
1001000011111 = 4639
1000011 = 67
11 = 3
11 = 3
11 = 3

Mathematica

ps = First@RealDigits[Pi, 2, 10^3]; lst = {}; Do[k = 1; While[fd = FromDigits[ Take[ps, k], 2]; EvenQ@fd || ! PrimeQ@fd, k++ ]; AppendTo[lst, fd]; j = 1; While[ ps[[j]] != 1, j++ ]; ps = Drop[ps, j], {n, 77}]; lst (* Robert G. Wilson v, Jul 24 2006 *)

Crossrefs

Cf. A004601, A068425, A117721, A065987.

Sequence in context: A012810 A364300 A020517 * A364116 A307232 A002667

Adjacent sequences: A119014 A119015 A119016 * A119018 A119019 A119020

Keyword

nonn,base

Author

Russell Walsmith, Jul 23 2006

Extensions

More terms from Robert G. Wilson v, Jul 24 2006

Status

approved