A161470 - OEIS

%I #20 Sep 08 2022 08:45:45

%S 5,17,53,2609,1604543,7625731721669,

%T 67585198634826967968486182915129003

%N Primes of the form 3^k+2^k+k^3-k^2.

%C The associated k are 1, 2, 3, 7, 13, 27, 73, 994, 1129, ... - _R. J. Mathar_, Jun 12 2009

%C The next term has 475 digits. - _Harvey P. Dale_, Dec 12 2010

%t A161470 = {}; Do[If[PrimeQ[p = (3^n + 2^n) + (n^3 - n^2)], AppendTo[A161470, p]], {n, 6!}]; A161470 (* Orlovsky *)

%t (* Alternate: *) Select[Table[3^k + 2^k + k^3 - k^2, {k, 2000}], PrimeQ] (* _Harvey P. Dale_, Dec 12 2010 *)

%o (Magma) [ a: n in [1..450] | IsPrime(a) where a is 3^n+2^n+n^3-n^2] // _Vincenzo Librandi_, Nov 30 2010

%Y Cf. A058765, A082101, A161469.

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Jun 10 2009

%E Definition simplified by _R. J. Mathar_, Jun 12 2009