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A230811 Smallest starting number for n consecutive odd numbers that are primes or strong pseudoprime (base 2). 0
3, 3, 3, 1640293473202755797 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

LINKS

Table of n, a(n) for n=1..4.

EXAMPLE

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

a(1) = 3: (3) ;

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

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

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

CROSSREFS

Cf. A001567, A001262, A230667, A230810.

Sequence in context: A015665 A230667 A131462 * A117032 A243823 A281141

Adjacent sequences:  A230808 A230809 A230810 * A230812 A230813 A230814

KEYWORD

nonn,hard,fini

AUTHOR

Shyam Sunder Gupta, Oct 30 2013

STATUS

approved

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Last modified October 15 19:25 EDT 2019. Contains 328037 sequences. (Running on oeis4.)