A145440 Primes of the form 8^k + 9.

17, 73, 521, 262153, 1073741833, 144115188075855881, 73786976294838206473, 273406340597876490546562778389702670669146178861651554553221325801244124899921990402939147127881737

Offset

1,1

Comments

8^k + 9 is prime for k = 1, 2, 3, 6, 10, 19, 22, ...

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..9

Example

For k=1, 8^1 + 9 =  17;
for n=2, 8^2 + 9 =  73;
for n=3, 8^3 + 9 = 521.

Mathematica

Select[8^Range[120]+9, PrimeQ]  (* Harvey P. Dale, Jan 18 2011 *)

Prog

(Magma) [a: n in [0..200] | IsPrime(a) where a is 8^n+9];

Crossrefs

A subsequence of A104070. Cf. A057196.

Sequence in context: A201610 A201262 A146658 * A112013 A165691 A154419

Adjacent sequences: A145437 A145438 A145439 * A145441 A145442 A145443

Keyword

nonn

Author

Vincenzo Librandi, Mar 11 2009

Status

approved