OFFSET
0,3
COMMENTS
Triple Mersenne numbers.
EXAMPLE
M(M(M(0)))=0
M(M(M(1)))=1
M(M(M(2)))=127
M(M(M(3)))=170141183460469231731687303715884105727
PROG
(PARI) for(x=0, 4, print(2^(2^(2^x-1)-1)-1))
CROSSREFS
KEYWORD
nonn
AUTHOR
Jorge Coveiro, Dec 24 2004
STATUS
approved