A221207 - OEIS

%I #37 Mar 17 2024 02:16:59

%S 2,17,2593,5308417,26214401,57802753,584652423169,5566277615617,

%T 24807731101697,2128654511374337,114923510727115685920505857,

%U 626707144888223764167681638401,28901765777295687591430290881352276511750619137

%N Primes of the form 2^(n-2)*(n+2)^2 + 1.

%e a(0) = 2 = 2^(0-2)*(0+2)^2 + 1 = (1/4) * 4 + 1.

%t Select[Table[2^(n - 2)*(n + 2)^2 + 1, {n, 0, 200}], PrimeQ] (* _T. D. Noe_, Apr 05 2013 *)

%o (PARI) for(n=0,1e3,is(ispseudoprime(t=2^(n-2)*(n + 2)^2+1), print1(t", "))) \\ _Charles R Greathouse IV_, Mar 18 2014

%K nonn,less

%O 1,1

%A _Irina Gerasimova_, Feb 21 2013