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A163589 Primes in the chain of repeated application of x->2*x+3, starting at x=1427. 0
1427, 2857, 5717, 11437, 22877, 45757, 183037, 366077, 732157, 23429117, 1499463677, 191931351037, 98268851732477, 393075406929917, 6289206510878717, 50313652087029757, 100627304174059517, 201254608348119037, 12880294934279618557 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

All primes created that way are congruent to 712 (mod 715).

Numbers in the chain may not be prime, for example 2*45757+3 = 91517.

The first primes congruent to 712 (mod 715) that are missed by the

chain are 10007, 15727 and 18587.

EXAMPLE

p=1427 is prime and put into the sequence. 2*1427+3 = 2857 is prime and put into the sequence.

2*2857+3=5717 is prime and put into the sequence.

MAPLE

x := 1427 ; for i from 1 to 80 do if isprime(x) then printf("%d, ", x) ; end if; x := 2*x+3 ; end do: # R. J. Mathar, Aug 02 2009

CROSSREFS

Sequence in context: A183780 A153426 A068572 * A156853 A094230 A060364

Adjacent sequences:  A163586 A163587 A163588 * A163590 A163591 A163592

KEYWORD

nonn

AUTHOR

Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Aug 01 2009

EXTENSIONS

Definition corrected by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Aug 01 2009

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Last modified February 14 03:37 EST 2012. Contains 205570 sequences.