%I A156895
%S A156895 3,7,31,271,4591,151471,9845551,326409519151,
%T A156895 16455349947998422816223361143099916435126171767057238357700938736968751
%N A156895 Primes of the form prod{2^n + 1, [n=0,1,2,3...]} + 1.
%C A156895 10th term has 150 digits. [From Emeric Deutsch (deutsch(AT)duke.poly.edu), 
               Mar 07 2009]
%e A156895 (2^0 + 1)*(2^1 + 1)*(2^2 + 1)*(2^3 + 1)*(2^4 + 1)= 2*3*5*9*17+ 1 = 4591
%p A156895 a := proc (n) if isprime(1+product(2^k+1, k = 0 .. n)) = true then 1+product(2^k+1, 
               k = 0 .. n) else end if end proc: seq(a(n), n = 0 .. 40); [From Emeric 
               Deutsch (deutsch(AT)duke.poly.edu), Mar 07 2009]
%Y A156895 Sequence in context: A030521 A105767 A063896 this_sequence A074047 A121810 
               A081475
%Y A156895 Adjacent sequences: A156892 A156893 A156894 this_sequence A156896 A156897 
               A156898
%K A156895 nonn
%O A156895 1,1
%A A156895 J. M. Bergot (thekingfishb(AT)yahoo.ca), Feb 17 2009
%E A156895 9th term added by Emeric Deutsch (deutsch(AT)duke.poly.edu), Mar 07 2009