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A163115 Primes of the form 2^n + 2*n + 1. 4
2, 5, 43, 8219, 36893488147419103363, 38685626227668133590597803, 862718293348820473429344482784628181556388621521298319395315527975371 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The corresponding values of n, i.e., 0, 1, 5, 13, 65, 85, 229, ... are of the form A192764() - 1. - Juri-Stepan Gerasimov, Jul 25 2011

The next term, a(8), has 604 digits. - Harvey P. Dale, Dec 17 2013

LINKS

Table of n, a(n) for n=1..7.

EXAMPLE

a(1) = 2^0 + 2*0 + 1 = 2.

a(2) = 2^1 + 2*1 + 1 = 5.

a(3) = 2^5 + 2*5 + 1 = 43.

a(4) = 2^13 + 2*13 + 1 = 8219.

MATHEMATICA

Select[Table[2^n+2n+1, {n, 0, 300}], PrimeQ] (* Harvey P. Dale, Dec 17 2013 *)

CROSSREFS

Sequence in context: A215170 A027730 A225724 * A221682 A088309 A056680

Adjacent sequences:  A163112 A163113 A163114 * A163116 A163117 A163118

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Jul 21 2009

EXTENSIONS

13 removed, 3 terms added by R. J. Mathar, Jul 27 2009

STATUS

approved

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Last modified May 27 11:14 EDT 2017. Contains 287204 sequences.