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A050920 Cullen primes: primes of the form n*2^n+1. 3
3, 393050634124102232869567034555427371542904833 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The next term is too large to display here, having 1423 digits. See A005849.

LINKS

Table of n, a(n) for n=1..2.

Ray Ballinger, Cullen Primes: Definition and Status

C. K. Caldwell, Cullen Primes

Eric Weisstein's World of Mathematics, Cullen Number

FORMULA

a(n) = A002064(A005849(n))

MATHEMATICA

lst={}; Do[If[PrimeQ[p=n*2^n+1], Print[p]; AppendTo[lst, p]], {n, 10^9}]; lst [From Vladimir Joseph Stephan Orlovsky, Aug 21 2008]

Select[Table[n*2^n+1, {n, 5000}], PrimeQ] (* Harvey P. Dale, Dec 14 2014 *)

CROSSREFS

See A005849 for more terms.

Sequence in context: A068740 A058473 A115527 * A001231 A141150 A089418

Adjacent sequences:  A050917 A050918 A050919 * A050921 A050922 A050923

KEYWORD

nonn,nice,bref,changed

AUTHOR

N. J. A. Sloane, Dec 30 1999

STATUS

approved

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Last modified December 19 19:12 EST 2014. Contains 252239 sequences.