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 A103071 Numbers n such that 8*10^n + R_n + 2 is prime, where R_n = 11...1 is the repunit (A002275) of length n. 1
 1, 10, 24, 199, 745, 7753, 17938, 21319, 24948, 26119, 29454, 51889, 62824, 88105 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Also numbers n such that (73*10^n+17)/9 is prime. a(15) > 10^5. - Robert Price, Oct 16 2015 LINKS Makoto Kamada, Prime numbers of the form 811...113. FORMULA a(n) = A101058(n) + 1. MATHEMATICA Do[ If[ PrimeQ[(73*10^n + 17)/9], Print[n]], {n, 0, 10000}] CROSSREFS Cf. A002275, A101058. Sequence in context: A261807 A135285 A235940 * A264296 A265150 A057462 Adjacent sequences:  A103068 A103069 A103070 * A103072 A103073 A103074 KEYWORD more,nonn AUTHOR Robert G. Wilson v, Jan 19 2005 EXTENSIONS a(7)-a(11) from Kamada data by Robert Price, Dec 14 2010 a(12)-a(14) from Robert Price, Oct 16 2015 STATUS approved

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Last modified February 26 08:33 EST 2020. Contains 332277 sequences. (Running on oeis4.)