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A174393 Numbers k such that 6*prime(k) -+ {1,5} are all prime. 0
1, 2, 4, 7, 106, 388, 930, 2999, 3127, 3974, 4982, 5154, 6350, 6612, 6750, 7661, 7693, 8783, 10156, 10465, 11989, 13101, 13266, 15349, 15351, 17476, 18087, 19305, 20670, 21434, 22671, 23134, 23613, 23667, 24493, 24509, 25780, 27474, 28764, 30457 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..40.

EXAMPLE

a(1)=1 because

  prime(1)*6 - 5 =  7,

  prime(1)*6 - 1 = 11,

  prime(1)*6 + 1 = 13, and

  prime(1)*6 + 5 = 17

are all prime.

MAPLE

isA174393 := proc(n) local p ; p := ithprime(n) ; isprime(p*6-1) and isprime(p*6-5) and isprime(p*6+1) and isprime(p*6+5); end proc: for n from 1 to 40000 do if isA174393(n) then printf("%d, ", n) ; end if; end do: # R. J. Mathar, Mar 29 2010

CROSSREFS

Sequence in context: A302938 A076719 A103009 * A153662 A222011 A063864

Adjacent sequences:  A174390 A174391 A174392 * A174394 A174395 A174396

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Mar 18 2010

EXTENSIONS

Corrected and extended by Charles R Greathouse IV, Mar 18 2010

STATUS

approved

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Last modified July 9 05:53 EDT 2020. Contains 335538 sequences. (Running on oeis4.)