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A130003 a(n) is the smallest natural number m such that 4^k + m is prime for all k=1,2,...,n. 0
1, 1, 3, 7, 7, 15, 37, 163, 177, 4503, 4503, 4503, 4503, 4503, 833021343, 12465115083, 95854279610863, 1158174141556287 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..18.

Carlos Rivera, 1(1198).4.1(3304).4441 .

Carlos Rivera, Puzzle 403. 833021343.

EXAMPLE

a(14)=4503 because 4^k + 4503 for 0<k<15 are prime and there is no smaller number with this property.

CROSSREFS

Cf. A130004.

Sequence in context: A175329 A081218 A240422 * A098581 A238997 A240260

Adjacent sequences:  A130000 A130001 A130002 * A130004 A130005 A130006

KEYWORD

hard,more,nonn

AUTHOR

Farideh Firoozbakht, May 30 2007, Jun 04 2007

EXTENSIONS

More terms from Jens Kruse Andersen, Jun 08 2007

STATUS

approved

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Last modified March 28 17:51 EDT 2020. Contains 333103 sequences. (Running on oeis4.)