%I #8 Dec 08 2016 20:44:57
%S 280743771536011781,666787209284980781,1386744766793550161,
%T 6558237049521329741,11646802313400102461
%N Smallest of 5 consecutive odd numbers that are primes or pseudoprime (base 2).
%C It is conjectured that all numbers in this sequence ends in 1.
%C All terms known so far are of the form A228455(n) - 4. - _M. F. Hasler_, Dec 08 2016
%e 280743771536011781 is in sequence because 280743771536011781, 280743771536011783, 280743771536011785, 280743771536011787, 280743771536011789 is a set of 5 consecutive odd number where 280743771536011785 is pseudoprime base 2 and others are prime.
%Y Cf. A001567, A228455.
%K nonn,hard,more
%O 1,1
%A _Shyam Sunder Gupta_, Oct 27 2013
%E Definition reworded by _M. F. Hasler_, Dec 08 2016