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 A102933 Numbers n such that 10^n + 3*R_n + 6 is prime, where R_n = 11...1 is the repunit (A002275) of length n. 1
 1, 2, 4, 7, 10, 13, 14, 22, 23, 29, 38, 50, 53, 67, 104, 350, 376, 412, 1205, 1835, 2510, 2668, 6097, 8296, 14296, 43369 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Also numbers n such that (4*10^n+17)/3 is prime. LINKS Makoto Kamada, Prime numbers of the form 133...339. FORMULA a(n) = A102014(n) + 1. MATHEMATICA Do[ If[ PrimeQ[(4*10^n + 17)/3], Print[n]], {n, 0, 10000}] CROSSREFS Cf. A002275, A102014. Sequence in context: A007303 A102988 A080137 * A122019 A190279 A186325 Adjacent sequences:  A102930 A102931 A102932 * A102934 A102935 A102936 KEYWORD more,nonn AUTHOR Robert G. Wilson v, Dec 16 2004 EXTENSIONS Addition of a(25) from Kamada data by Robert Price, Dec 08 2010 a(26) from Erik Branger May 01 2013 by Ray Chandler, Aug 16 2013 STATUS approved

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Last modified May 17 09:03 EDT 2021. Contains 343969 sequences. (Running on oeis4.)