A138943 Primes of the form (16^k - 3^k)/13.

19, 313, 1635972917889127228189253483929940713

Offset: 1

Author

Vladimir Joseph Stephan Orlovsky, May 16 2008

Keywords

• nonn

Comments

The next term has 562 digits. - Harvey P. Dale, Mar 28 2013

Links

• Amiram Eldar, Table of n, a(n) for n = 1..4

Crossrefs

Cf. A128030, A180845.

Programs

Mathematica

a={};Do[p=(16^n-3^n)/13; If[PrimeQ[p], AppendTo[a,p]], {n,1,10^2}];a
Select[Table[(16^n-3^n)/13,{n,500}],PrimeQ] (* Harvey P. Dale, Mar 28 2013 *)

Formula

a(n) = A180845(A128030(n)). - Amiram Eldar, Jul 11 2025