A230667 Smallest starting number for n consecutive odd numbers that are primes or pseudoprime (base 2).

3, 3, 3, 641, 280743771536011781

Offset: 1

Author

Shyam Sunder Gupta, Oct 27 2013

Keywords

• nonn
• hard

Comments

It is conjectured that the sequence is full, that is, a(6) does not exist.

Examples

			First and smallest occurrence of n, n >= 1, consecutive odd numbers that are primes or pseudoprimes (base 2):
a(1) = 3: (3) ;
a(2) = 3: (3, 5) ;
a(3) = 3: (3, 5, 7);
a(4) = 641: (641, 643, 645, 647); (645 is pseudoprime base 2 and others are prime);
a(5) = 280743771536011781: (280743771536011781, 280743771536011783, 280743771536011785, 280743771536011787, 280743771536011789); (280743771536011785 is pseudoprime base 2 and others are prime).
		

Crossrefs

Cf. A001567, A228455.