A199192 - OEIS

A199192

Primes of the form 3^(2n-3)+3^(n-1)+1.

7, 37, 271, 2269, 19927, 129159847, 1162320517, 49269609804781974450852068861184694669, 589881151426658740854227725580736348850640632297373414091790995505756623268837

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OFFSET

1,1

COMMENTS

The corresponding n are in A199191.

The next term -- a(10) -- has 152 digits. - Harvey P. Dale, May 28 2015

LINKS

Table of n, a(n) for n=1..9.

FORMULA

Primes in A198410.

MATHEMATICA

a={}; Do[p=( (3^(n-1) + 1)^3 -1)/3^n; If[PrimeQ[p], AppendTo[a, p]], {n, 10^2}]; Print[a];

Select[Table[3^(2n-3)+3^(n-1)+1, {n, 100}], PrimeQ] (* Harvey P. Dale, May 28 2015 *)

CROSSREFS

Cf. A198410, A199191.

Sequence in context: A217723 A100309 A198410 * A089677 A075996 A356127

Adjacent sequences: A199189 A199190 A199191 * A199193 A199194 A199195

KEYWORD

nonn

AUTHOR

Michel Lagneau, Nov 03 2011

STATUS

approved