OFFSET
1,1
COMMENTS
LINKS
Jinyuan Wang, Table of n, a(n) for n = 1..16
MATHEMATICA
Differences[2^(Select[Range[512], PrimeQ[2^#-1]&]-1), 2] (* Harvey P. Dale, Oct 15 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Omar E. Pol, Apr 18 2008
EXTENSIONS
a(6) corrected and more terms from Joerg Arndt, Jul 09 2017
STATUS
approved