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 A082707 Numbers k such that (32*10^(k-1) - 23)/9 is a plateau prime. 1
 3, 9, 141, 231, 427, 463, 727, 1975, 7231, 45861, 47305 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Prime versus probable prime status and proofs are given in the author's table. REFERENCES C. Caldwell and H. Dubner, "Journal of Recreational Mathematics", Volume 28, No. 1, 1996-97, pp. 1-9. LINKS Patrick De Geest, PDP Reference Table - 353. Makoto Kamada, Prime numbers of the form 355...553. FORMULA a(n) = A056254(n) + 2. EXAMPLE k=9 -> (32*10^(9-1) - 23)/9 = 355555553. CROSSREFS Cf. A082697-A082720, A056254. Sequence in context: A288757 A289900 A235062 * A087193 A217638 A101967 Adjacent sequences:  A082704 A082705 A082706 * A082708 A082709 A082710 KEYWORD nonn,base,hard,more AUTHOR Patrick De Geest, Apr 13 2003 EXTENSIONS More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008 Edited by Ray Chandler, Nov 05 2014 STATUS approved

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Last modified February 29 02:35 EST 2020. Contains 332353 sequences. (Running on oeis4.)