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Numbers k such that prime(k)^2 + k! is prime.
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%I #24 Dec 02 2024 10:10:42

%S 1,2,3,4,5,13,14,18,32,48,49,275,1423,1750,4896,13682

%N Numbers k such that prime(k)^2 + k! is prime.

%t lst={};Do[p=Prime[n];If[PrimeQ[p^2+n! ], AppendTo[lst, n]], {n, 3*10^2}];lst (* _Vladimir Joseph Stephan Orlovsky_, Sep 08 2008 *)

%t Select[Range[280],PrimeQ[Prime[#]^2+#!]&] (* _Harvey P. Dale_, Apr 24 2018 *)

%o (PARI) j=[]; for(n=1,300, if(isprime(prime(n)^2+n!), j=concat(j, n))); j

%K nonn,more

%O 1,2

%A _Alexander R. Povolotsky_, Aug 09 2008

%E Offset changed to 1 by and a(13)-a(14) from _Jinyuan Wang_, Apr 10 2020

%E a(15) from _Michael S. Branicky_, Apr 25 2023

%E a(16) from _Michael S. Branicky_, Dec 01 2024