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Indices of Apery-primes: numbers n such that the concatenation of the first n decimal digits of Apery's constant zeta(3) is prime.
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%I #10 Feb 16 2025 08:33:01

%S 10,55,109,141

%N Indices of Apery-primes: numbers n such that the concatenation of the first n decimal digits of Apery's constant zeta(3) is prime.

%C No additional terms up to 10000. - _Harvey P. Dale_, Aug 28 2019

%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Apery-Prime.html">Apery-Prime</a>

%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/IntegerSequencePrimes.html">Integer Sequence Primes</a>

%e zeta(3) = 1.2020569031595..., 1202056903--the concatenation of the first 10 decimal digits--is prime, so a(1)=10.

%t Module[{nn=10000,z},z=RealDigits[Zeta[3],10,nn][[1]];Select[Range[nn],PrimeQ[FromDigits[Take[z,#]]]&]] (* _Harvey P. Dale_, Aug 28 2019 *)

%Y Cf. A002117, A119333.

%K nonn,more,base,changed

%O 1,1

%A _Eric W. Weisstein_, May 14 2006

%E Edited by _Charles R Greathouse IV_, Apr 27 2010