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A130800 Numbers n such that both 2n+1 and 3n+1 are primes. 2
2, 6, 14, 20, 26, 36, 50, 54, 74, 90, 116, 140, 146, 174, 200, 204, 210, 224, 230, 270, 284, 306, 330, 336, 350, 354, 384, 404, 410, 426, 440, 476, 510, 516, 554, 564, 596, 600, 624, 644, 650, 704, 714, 726, 740, 746, 834, 846, 894, 930, 944, 950, 1026, 1040 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

MATHEMATICA

Select[Range[1100], AllTrue[{2, 3}#+1, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, May 17 2016 *)

PROG

(MAGMA) [n: n in [0..500] | IsPrime(2*n+1) and IsPrime(3*n+1)]; // Vincenzo Librandi, Nov 23 2010

CROSSREFS

Sequence in context: A246068 A032643 A067664 * A067262 A107369 A151731

Adjacent sequences:  A130797 A130798 A130799 * A130801 A130802 A130803

KEYWORD

nonn

AUTHOR

Max Alekseyev, Jul 18 2007

EXTENSIONS

More terms from Vincenzo Librandi, Mar 26 2010

STATUS

approved

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Last modified February 21 12:59 EST 2018. Contains 299411 sequences. (Running on oeis4.)