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 A046843 Numbers n such that n*2^n-n-1 is prime. 2
 2, 4, 8, 12, 16, 40, 80, 314, 478, 604, 634, 790, 868, 1264, 1376, 2536, 3544, 6564, 7268, 7780, 8366 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The corresponding primes are given in A046842. LINKS MAPLE A046843:=n->`if`(isprime(n*2^n-n-1), n, NULL): seq(A046843(n), n=1..1000); # Wesley Ivan Hurt, Oct 12 2014 MATHEMATICA Select[Range[10000], PrimeQ[# 2^#-#-1]&] (* Harvey P. Dale, Oct 10 2011 *) PROG (PARI) is(n)=ispseudoprime(n*2^n-n-1) \\ Charles R Greathouse IV, May 22 2017 CROSSREFS Cf. A046842. Sequence in context: A152768 A266047 A273109 * A292060 A152125 A305694 Adjacent sequences:  A046840 A046841 A046842 * A046844 A046845 A046846 KEYWORD nonn,more AUTHOR EXTENSIONS Sign in definition corrected by R. J. Mathar, Oct 10 2010 More terms from Harvey P. Dale, Oct 10 2011 STATUS approved

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Last modified January 23 06:15 EST 2019. Contains 319374 sequences. (Running on oeis4.)