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A230668 Smallest of 5 consecutive odd numbers that are primes or pseudoprime (base 2). 3

%I

%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

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Last modified May 21 00:36 EDT 2022. Contains 353886 sequences. (Running on oeis4.)