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A002234
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Numbers n such that the Woodall number n*2^n - 1 is prime.
(Formerly M0820 N0311)
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8
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2, 3, 6, 30, 75, 81, 115, 123, 249, 362, 384, 462, 512, 751, 822, 5312, 7755, 9531, 12379, 15822, 18885, 22971, 23005, 98726, 143018, 151023, 667071, 1195203, 1268979, 1467763, 2013992, 2367906, 3752948
(list;
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listen;
history;
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internal format)
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OFFSET
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1,1
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COMMENTS
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No other terms < 6500000 - John Blazek, May 14 2009
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REFERENCES
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J.-M. De Koninck, Ces nombres qui nous fascinent, Entry 115, p. 40, Ellipses, Paris 2008.
H. Riesel, Lucasian criteria for the primality of N=h.2^n-1, Math. Comp., 23 (1969), 869-875.
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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LINKS
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Table of n, a(n) for n=1..33.
Ray Ballinger, Woodall Primes: Definition and Status
Ray Ballinger and Wilfrid Keller, Woodall numbers
C. K. Caldwell, Woodall Numbers
J. DeMaio, Generalized Woodall Numbers
R. Ondrejka, The Top Ten: a Catalogue of Primal Configurations
Eric Weisstein's World of Mathematics, Woodall Numbers
Eric Weisstein's World of Mathematics, Integer Sequence Primes
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CROSSREFS
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Cf. A050918 (for the actual primes), A003261, A005849.
Sequence in context: A051717 A192441 A108326 * A074005 A145499 A221310
Adjacent sequences: A002231 A002232 A002233 * A002235 A002236 A002237
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KEYWORD
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nonn,nice,hard
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AUTHOR
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N. J. A. Sloane, Simon Plouffe
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EXTENSIONS
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a(27) communicated by Mohammed Bouayoun (bouyao(AT)wanadoo.fr), Mar 15 2004
1195203 found by M. Rodenkirch, but the region from 1020000 to 1195203 is incompletely searched; contributed by Eric W. Weisstein, Nov 29, 2005
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 05 2008
1467763, 2013992, 2367906, 3752948 from John Blazek, May 14 2009
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STATUS
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approved
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