A101331 - OEIS

%I #3 Jan 21 2019 19:01:55

%S 3,5,257,340282366920938463463374607431768211457

%N Fermat(Mersenne(x)) = 2^(2^(2^x-1))+1

%C Fermat-Mersenne numbers.

%e F(M(0))= 3

%e F(M(1))= 5

%e F(M(2))= 257

%e F(M(3))= 340282366920938463463374607431768211457

%o (PARI) for(x=0,4,print( ( 2^(2^(2^x-1))+1 )))

%K nonn

%O 0,1

%A _Jorge Coveiro_, Dec 24 2004