A282973 Primes in A011546.

3, 31, 314159, 314159265359

Offset: 1

Author

XU Pingya, Feb 25 2017

Keywords

• nonn
• base

Examples

			a(5) = A011546(1902) = 314159...066118631 is a prime with 1902 digits.
a(6) = A011546(3971) = 314159...411010447.
a(7) = A011546(5827) = 314159...690496521.
a(8) = A011546(16208) = A005042(5) = 314159....943936307.
For n<=17511, there are eight primes in sequence A011546(n).
In addition, because of round(Pi*10^47576) = floor(Pi*10^47576), and A011546(47577)(=A005042(6)) is a prime. Thus,  A011546(47577) will appear in here. A011546(613373)(=A005042(8)) as well. But A011546(78073)(=A005042(7)+1) is not prime.
		

Links

• Eric Weisstein's World of Mathematics, Pi-Prime

Crossrefs

Cf. A011546, A282974, A000796, A005042.

Programs

Mathematica

Do[If[PrimeQ[Round[Pi*10^(n-1)]],Print[Round[Pi*10^(n-1)]]],{n,17511}]
Select[Module[{nn=20,pid},pid=RealDigits[Pi,10,nn+2][[1]];Table[Floor[(FromDigits[ Take[ pid,n+1]])/10+1/2],{n,nn}]],PrimeQ] (* Harvey P. Dale, Jan 01 2023 *)