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%I #16 Apr 11 2021 05:05:04
%S 5,29,88,948,1071,1100,1578,14357
%N Integers k such that ceiling(Pi^k) is prime.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Phi-Prime.html">Phi-Prime</a>
%e a(1)=5: ceiling(3.14159265...^5) = ceiling(306.0196847...) = 307, which is prime.
%t $MaxExtraPrecision = 2^20; Do[ If[ PrimeQ[ Ceiling[Pi^n]], Print[n]], {n, 10000}] (* _Robert G. Wilson v_, Nov 28 2005 *)
%Y Cf. A001673.
%K nonn,more
%O 1,1
%A _Ray G. Opao_, Nov 27 2005
%E a(5)-a(7) from _Robert G. Wilson v_, Nov 28 2005
%E a(8) from _Donovan Johnson_, Feb 04 2008