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A124487 Numbers k such that 2*k-1, 4*k-1, 6*k-1 and 8*k-1 are primes. 2
3, 45, 705, 945, 5295, 5775, 5955, 6450, 8580, 9945, 11175, 12120, 13095, 18000, 18525, 18690, 19710, 22440, 22785, 24960, 30390, 33780, 34335, 37665, 41790, 44460, 52185, 54180, 56175, 57300, 63570, 66990, 67515, 67725, 73335, 74700 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

MATHEMATICA

Select[Range[80000], And @@ PrimeQ /@ ({2, 4, 6, 8}*# - 1) &] (* Ray Chandler, Nov 21 2006 *)

CROSSREFS

Cf. A124485-A124492.

Sequence in context: A076140 A131568 A287031 * A266698 A132303 A298799

Adjacent sequences:  A124484 A124485 A124486 * A124488 A124489 A124490

KEYWORD

nonn

AUTHOR

Artur Jasinski, Nov 04 2006

EXTENSIONS

Extended by Ray Chandler, Nov 21 2006

STATUS

approved

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Last modified December 2 10:39 EST 2020. Contains 338876 sequences. (Running on oeis4.)