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A269018 Primes p of the form 2^n + 2*(-1)^n - 1. 1
2, 5, 17, 29, 257, 509, 65537, 536870909, 13164036458569648337239753460458804039861886925068638906788872189, 3369993333393829974333376885877453834204643052817571560137951281149, 13803492693581127574869511724554050904902217944340773110325048447598589 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Corresponding values of n: 0, (2, 3), 4, 5, 8, 9, 16, 29, 213, 221, 233, ...; for the prime 5 there are two values 2 and 3.

Fermat primes > 3 from A019434 are terms.

Prime terms from A269019.

Conjecture: union of {2} , {A019434(n) for n > 1} and {A176680(n)}.

LINKS

Table of n, a(n) for n=1..11.

PROG

(MAGMA) Set(Sort([2^n + 2*(-1)^n - 1: n in [0..300] | IsPrime(2^n + 2*(-1)^n - 1)]))

CROSSREFS

Cf. A019434, A052539, A092506, A176680, A267921, A269019.

Sequence in context: A106882 A172122 A101009 * A066649 A075345 A045705

Adjacent sequences:  A269015 A269016 A269017 * A269019 A269020 A269021

KEYWORD

nonn

AUTHOR

Jaroslav Krizek, Feb 17 2016

STATUS

approved

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Last modified December 1 16:07 EST 2021. Contains 349430 sequences. (Running on oeis4.)