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Smallest starting number for n consecutive odd numbers that are primes or strong pseudoprime (base 2).
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%I #7 Oct 30 2013 21:58:09

%S 3,3,3,1640293473202755797

%N Smallest starting number for n consecutive odd numbers that are primes or strong pseudoprime (base 2).

%C It is conjectured that there can be at most one more term, a(5).

%e First and smallest occurrence of n, n >= 1, consecutive odd numbers that are primes or strong pseudoprime (base 2):

%e a(1) = 3: (3) ;

%e a(2) = 3: (3, 5) ;

%e a(3) = 3: (3, 5, 7);

%e a(4) = 1640293473202755797: (1640293473202755797, 1640293473202755799, 1640293473202755801, 1640293473202755803); (1640293473202755801 is strong pseudoprime base 2 and others are prime);

%Y Cf. A001567, A001262, A230667, A230810.

%K nonn,hard,fini

%O 1,1

%A _Shyam Sunder Gupta_, Oct 30 2013