A067904 Primes of the form floor((3/2)^k).

2, 3, 5, 7, 11, 17, 4987, 7481, 180693856682317883, 4630985912862061063, 75677449184722757264165738713, 1910944005427272291238064043761449, 366425537175409658704814112327931286021

Offset: 1

Author

Benoit Cloitre, Mar 03 2002

Keywords

• nonn

References

• R. K. Guy, Unsolved Problems in Number Theory, E19.

Links

• Charles R Greathouse IV, Table of n, a(n) for n = 1..23

Crossrefs

Cf. A043037, A070758, A070759.

Programs

Mathematica

f[n_]:=Floor[(3/2)^n]; lst={};Do[p=f[n];If[PrimeQ[p],AppendTo[lst,p]],{n,0,4*5!}];lst (* Vladimir Joseph Stephan Orlovsky, Jul 02 2009 *)
Select[Floor[(3/2)^Range[300]],PrimeQ] (* Harvey P. Dale, Dec 28 2014 *)

PARI

v=[];for(k=2,5700, if(ispseudoprime(t=floor((3/2)^k)), v=concat(v,t))); v \\ Charles R Greathouse IV, Feb 15 2011