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A153779 Numbers of the form 49*k, where 49*k+2 and 49*k-6 are both prime. 1
2009, 4655, 4949, 9065, 9947, 13475, 14945, 15239, 17297, 25235, 26117, 32585, 33467, 37877, 39935, 44639, 47285, 52577, 56399, 59339, 59927, 61985, 62867, 64925, 72275, 75215, 75509, 76097, 79037, 82565, 86387, 89915, 92855, 94619 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..1000

FORMULA

a(n) >> n log^2 n. - Charles R Greathouse IV, Aug 28 2016

EXAMPLE

2009 = 49*41 and both 2003 and 2011 are prime.

MATHEMATICA

49*Select[Range[115000], PrimeQ[49*# + 2] && PrimeQ[49*# - 6] &] (* G. C. Greubel, Aug 28 2016 *)

PROG

(PARI) is(n)=n%294==245 && isprime(n+2) && isprime(n-6) \\ Charles R Greathouse IV, Aug 28 2016

CROSSREFS

Sequence in context: A172780 A172807 A153822 * A162242 A249955 A020433

Adjacent sequences:  A153776 A153777 A153778 * A153780 A153781 A153782

KEYWORD

nonn

AUTHOR

John L. Drost, Jan 01 2009

STATUS

approved

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Last modified July 15 22:48 EDT 2019. Contains 325061 sequences. (Running on oeis4.)