OFFSET
1,1
COMMENTS
The next term a(10) = 2^2072-2073 has 624 decimal digits.
a(11) has 1882 decimal digits. - Vincenzo Librandi, Jul 18 2012
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..10
MATHEMATICA
Select[Table[2^n-n-1, {n, 0, 7000}], PrimeQ] (* Vincenzo Librandi, Jul 18 2012 *)
PROG
(Magma) [ a: n in [1..200] | IsPrime(a) where a is 2^n-n-1 ]; // Vincenzo Librandi, Jul 18 2012
CROSSREFS
KEYWORD
nonn
AUTHOR
Hugo Pfoertner, Oct 18 2004
STATUS
approved