OFFSET
1,1
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..15
EXAMPLE
a(4) = 82677 because the first 4 Mersenne primes are 2^2-1=3, 2^3-1=7, 2^5-1=31, 2^7-1=127; 3*7*31*127 = 82677.
MATHEMATICA
FoldList[Times, 1, Select[Table[2^n-1, {n, Prime[Range[50]]}], PrimeQ]] (* Harvey P. Dale, Jul 10 2013 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Pierre CAMI, Oct 17 2004
EXTENSIONS
More terms from Harvey P. Dale, Jul 10 2013
STATUS
approved