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A024892 Numbers n such that 3*n+1 is prime. 8
2, 4, 6, 10, 12, 14, 20, 22, 24, 26, 32, 34, 36, 42, 46, 50, 52, 54, 60, 64, 66, 70, 74, 76, 80, 90, 92, 94, 102, 104, 110, 112, 116, 122, 124, 126, 132, 136, 140, 144, 146, 152, 154, 162, 166, 174, 180, 182, 190, 192, 200, 202, 204, 206, 210, 214, 220, 224, 230, 236, 242, 244, 246 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

FORMULA

a(n) = 2*A024899(n) = A034936(n)+1

MATHEMATICA

lst={}; Do[p=3*n+1; If[PrimeQ[p], AppendTo[lst, n]], {n, 0, 10^3}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Sep 10 2008]

PROG

(MAGMA) [n: n in [1..1000] | IsPrime(3*n+1)] [From Vincenzo Librandi, Nov 20 2010]

CROSSREFS

A002476 gives primes, A091178 gives prime index.

Sequence in context: A141104 A047410 A164875 * A087136 A015921 A132631

Adjacent sequences:  A024889 A024890 A024891 * A024893 A024894 A024895

KEYWORD

nonn

AUTHOR

Clark Kimberling (ck6(AT)evansville.edu)

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Last modified February 16 21:51 EST 2012. Contains 205978 sequences.