The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A200821 Numbers n such that (2^n + n)*2^n - 1 is prime. 7
 1, 2, 34, 107, 1568, 1933, 3551, 6793 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The generalization of this sequence is possible with the primes of the form  (b^n +-k)*b^n +-1. LINKS Henri Lifchitz, New forms of primes EXAMPLE 2 is in the sequence because (2^2 + 2)*2^2 - 1 = 23 is prime. MATHEMATICA lst={}; Do[If[PrimeQ[(2^n + n)*2^n-1], AppendTo[lst, n]], {n, 10000}]; lst PROG (PARI) is(n)=ispseudoprime((2^n+n)<

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified September 25 06:32 EDT 2020. Contains 337335 sequences. (Running on oeis4.)