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%I #26 Mar 26 2024 11:16:29
%S 3,7,53,1619,821641,104484802057,870566678511500413493
%N a(n) = prime(2^(2^n)).
%C An estimate using the program in A121046 for a(7) is 3.13863199556707166...*10^40. - _Hugo Pfoertner_, Mar 26 2024
%H Andrew Booker, <a href="https://t5k.org/nthprime/index.php#n-th">The Nth Prime Page</a>.
%F a(n) = A000040(A001146(n)). - _Michel Marcus_, Mar 25 2024
%F a(n) = A033844(2^n). - _Rainer Rosenthal_, Mar 25 2024
%t Table[Prime[2^(2^n)],{n,0,5}] (* _Harvey P. Dale_, Oct 13 2013 *)
%o (PARI) f(n) = for(x=0,n,print1(prime(2^2^x)","))
%Y Cf. A000040, A001146, A033844.
%K nonn,hard,more
%O 0,1
%A _Cino Hilliard_, Jun 19 2004
%E a(6) from _Rainer Rosenthal_, Mar 25 2024