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A082704
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Numbers k such that (28*10^(k-1) + 17)/9 is a depression prime.
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2
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OFFSET
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1,1
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COMMENTS
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Prime versus probable prime status and proofs are given in the author's table.
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REFERENCES
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C. Caldwell and H. Dubner, "Journal of Recreational Mathematics", Volume 28, No. 1, 1996-97, pp. 1-9.
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LINKS
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Table of n, a(n) for n=1..9.
Patrick De Geest, PDP Reference Table - 313.
Makoto Kamada, Prime numbers of the form 311...113.
Index entries for primes involving repunits.
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FORMULA
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a(n) = A056251(n) + 2.
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EXAMPLE
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k=15 -> (28*10^(15-1) + 17)/9 = 311111111111113.
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CROSSREFS
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Cf. A082697-A082720, A056251, A068650.
Sequence in context: A113487 A032623 A146512 * A152270 A032919 A340018
Adjacent sequences: A082701 A082702 A082703 * A082705 A082706 A082707
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KEYWORD
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nonn,base,more
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AUTHOR
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Patrick De Geest, Apr 13 2003
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EXTENSIONS
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Edited by Ray Chandler, Nov 04 2014
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STATUS
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approved
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