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A081296 Primes of the form 2^k - k. 9
2, 5, 503, 8179, 524269, 2097131, 36028797018963913, 3705346855594118253554271520278013051304639509300498049262642688253220148477691 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes in A000325.

The corresponding k are given in A048744.

Next term a(9) contains roughly 1000 digits and is too large to include. - R. J. Mathar, Jul 15 2007

LINKS

Table of n, a(n) for n=1..8.

FORMULA

a(n)=2^A048744(n)-A048744(n). [From R. J. Mathar, Jul 22 2009]

MATHEMATICA

lst={}; s=1; Do[s+=(n+=s); If[PrimeQ[Abs[s]], AppendTo[lst, s]], {n, 0, 6!}]; lst (* Vladimir Joseph Stephan Orlovsky, Oct 11 2008 *)

Select[Table[2^n-n, {n, 300}], PrimeQ] (* Harvey P. Dale, Nov 24 2018 *)

PROG

(PARI) { for(k=1, 100000, if(isprime(2^k-k), print1(2^k-k, ", "))); } \\ R. J. Mathar, Jul 15 2007

CROSSREFS

Cf. A048744 (n such that 2^n - n is prime).

Sequence in context: A208211 A138696 A163798 * A133378 A283561 A037063

Adjacent sequences:  A081293 A081294 A081295 * A081297 A081298 A081299

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Apr 20 2003

EXTENSIONS

More terms from R. J. Mathar, Jul 15 2007

STATUS

approved

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Last modified June 16 07:14 EDT 2019. Contains 324145 sequences. (Running on oeis4.)