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%I #11 Mar 07 2024 11:55:09
%S 3,73,4639,67,3,3,3,3,3,5,3,5,5,5,17,17,1069,5,3,5,17,3,9099300883537,
%T 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,
%U 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
%N 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.
%C Records: 3, 73, 4649, 9099300883537, 37848784972821936516494858855515680431107854546647118951099098009925403829863969526043052181881, ..., . - _Robert G. Wilson v_, Jul 24 2006
%e 11 = 3
%e 1001001 = 73
%e 1001000011111 = 4639
%e 1000011 = 67
%e 11 = 3
%e 11 = 3
%e 11 = 3
%t 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 *)
%Y Cf. A004601, A068425, A117721, A065987.
%K nonn,base
%O 1,1
%A _Russell Walsmith_, Jul 23 2006
%E More terms from _Robert G. Wilson v_, Jul 24 2006