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 A082705 Numbers k such that (29*10^(k-1) + 7)/9 is a depression prime. 1
 7, 9, 895, 1525, 3037, 21157 (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 - 323. Makoto Kamada, Prime numbers of the form 322...223. FORMULA a(n) = A056252(n) + 2. EXAMPLE k=9 -> (29*10^(9-1) + 7)/9 = 322222223. CROSSREFS Cf. A082697-A082720, A056252. Sequence in context: A306184 A027723 A046265 * A122577 A180732 A266551 Adjacent sequences:  A082702 A082703 A082704 * A082706 A082707 A082708 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 December 6 16:24 EST 2019. Contains 329808 sequences. (Running on oeis4.)