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A050528 Primes of the form 9*2^n+1. 2
19, 37, 73, 577, 1153, 18433, 147457, 1179649, 77309411329, 39582418599937, 79164837199873, 83010348331692982273, 332041393326771929089, 1328165573307087716353, 21760664753063325144711169, 196002643346460554954903773880698489798657 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..25

Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime

MAPLE

A050528:=n->`if`(isprime(9*2^n+1), 9*2^n+1, NULL): seq(A050528(n), n=1..200); # Wesley Ivan Hurt, Aug 09 2014

MATHEMATICA

Select[9*2^Range[150]+1, PrimeQ] (* Harvey P. Dale, Aug 08 2014 *)

PROG

(MAGMA) [a: n in [0..150] | IsPrime(a) where a is (9*2^n+1) ]; // Vincenzo Librandi, Aug 09 2014

CROSSREFS

For more terms see A002256.

Sequence in context: A158293 A107579 A245381 * A053685 A244111 A136063

Adjacent sequences:  A050525 A050526 A050527 * A050529 A050530 A050531

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Dec 29 1999

STATUS

approved

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Last modified December 21 20:27 EST 2014. Contains 252326 sequences.