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 A058775 Numbers n such that n * 2^(n/2) - 1 is prime. 0
 2, 6, 8, 20, 54, 68, 468, 648, 1100, 1374, 14072, 17790, 20038, 27192, 42692 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 REFERENCES Posting to NMBRTHRY(AT)LISTSERV.NODAK.EDU by Mike Oakes Dec 30 2000 entitled "Gaussian analogues of the Cullen and Woodall primes." LINKS MATHEMATICA Do[ If[ PrimeQ[n*2^(n/2) - 1], Print[n] ], {n, 1, 100000} ] Select[Range[2, 43000, 2], PrimeQ[#*2^(#/2)-1]&] (* Harvey P. Dale, Dec 13 2018 *) PROG (PARI) is(n)=isprime(n*2^(n/2)-1) \\ Charles R Greathouse IV, Jun 13 2017 CROSSREFS Sequence in context: A289095 A290160 A290213 * A103023 A111247 A045656 Adjacent sequences:  A058772 A058773 A058774 * A058776 A058777 A058778 KEYWORD nonn,easy AUTHOR Robert G. Wilson v, Jan 02 2001 STATUS approved

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Last modified January 16 15:53 EST 2019. Contains 319195 sequences. (Running on oeis4.)