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A057738 Primes p such that 3^p + 2 is prime. 2
2, 3, 139 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

No other terms below 2*10^5.

Primes in A051783. - Jens Kruse Andersen, Jun 29 2014

REFERENCES

J.-M. De Koninck, Ces nombres qui nous fascinent, Entry 139, p. 48, Ellipses, Paris 2008.

LINKS

Table of n, a(n) for n=1..3.

EXAMPLE

a(2) = 3 because 3^3 + 2 = 29 is prime.

MATHEMATICA

For[n = 1, n < 700, n++, If[PrimeQ[3^Prime[n] + 2], Print[Prime[n]]]] (* Stefan Steinerberger, Mar 18 2006 *)

PROG

(MAGMA) [p: p in PrimesUpTo(2000) | IsPrime(3^p+2)]; // Vincenzo Librandi, Jun 30 2014

CROSSREFS

Cf. A051783, A057739.

Sequence in context: A010343 A118169 A066908 * A234999 A254787 A042073

Adjacent sequences:  A057735 A057736 A057737 * A057739 A057740 A057741

KEYWORD

more,nonn,bref

AUTHOR

G. L. Honaker, Jr., Oct 29 2000

EXTENSIONS

Lower bound for the next term updated by Max Alekseyev, Jun 14 2011

STATUS

approved

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Last modified February 26 09:05 EST 2020. Contains 332277 sequences. (Running on oeis4.)