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Primes of the form 3^n-n^3.
3

%I #3 Mar 31 2012 12:38:25

%S 2,17,58049,6461081889226673298791633,

%T 273892744995340833777347939263771534786080723598328513,

%U 141158163862183763292171284564016760661754655311572624335224092241585052457078933432718798844633407313

%N Primes of the form 3^n-n^3.

%C Generated by the n of A109387. The number of decimal digits in this sequence grows as 1, 2, 5, 25, 54, 102, 166, 194,...

%C The large terms beyond a(6) are not shown.

%t f[n_]:=3^n-n^3; lst={};Do[If[PrimeQ[f[n]],AppendTo[lst,f[n]]],{n,4*5!}]; lst

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Jul 24 2009

%E Edited by _R. J. Mathar_, Jul 26 2009