%I
%S 3,3,3,641,280743771536011781
%N Smallest starting number for n consecutive odd numbers that are primes or pseudoprime (base 2).
%C It is conjectured that the sequence is full, that is, a(6) does not exist.
%e First and smallest occurrence of n, n >= 1, consecutive odd numbers that are primes or pseudoprimes (base 2):
%e a(1) = 3: (3) ;
%e a(2) = 3: (3, 5) ;
%e a(3) = 3: (3, 5, 7);
%e a(4) = 641: (641, 643, 645, 647); (645 is pseudoprime base 2 and others are prime);
%e a(5) = 280743771536011781: (280743771536011781, 280743771536011783, 280743771536011785, 280743771536011787, 280743771536011789); (280743771536011785 is pseudoprime base 2 and others are prime).
%Y Cf. A001567, A228455.
%K nonn,hard
%O 1,1
%A _Shyam Sunder Gupta_, Oct 27 2013
