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%I #22 Jul 24 2024 15:09:28
%S 0,1,3,8,21,32,33,48,68,295,296,298,1081,1753,1963,4336,5008,5608,
%T 14240
%N Numbers k such that 23*10^(k + 2) + 57 is prime.
%C a(20) > 40000. - _Michael S. Branicky_, Jul 24 2024
%t lst = {}; Do[ If[ PrimeQ[23*10^(n + 2) + 57], AppendTo[ lst, n]], {n, 0, 6000}]; lst (* _Robert G. Wilson v_, May 29 2009 *)
%Y Cf. A160403 (primes of the form 23*10^(k + 2) + 57).
%K nonn,base,more
%O 1,3
%A _Lekraj Beedassy_, May 13 2009
%E a(8)-a(18) from _Robert G. Wilson v_, May 29 2009
%E Name edited by _Jinyuan Wang_, Aug 10 2021
%E a(19) from _Michael S. Branicky_, Mar 10 2023