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 A119986 Least positive k such that k * 10^n + prime(n) is prime. 0
 1, 6, 19, 5, 6, 17, 6, 6, 10, 2, 15, 17, 3, 9, 7, 48, 32, 12, 39, 9, 17, 18, 27, 1, 50, 36, 18, 3, 11, 44, 19, 45, 46, 78, 36, 36, 5, 20, 33, 41, 127, 42, 12, 63, 16, 33, 31, 42, 8, 6, 98, 57, 21, 47, 22, 91, 21, 45, 24, 1, 3, 12, 72, 57, 51, 129, 351, 8, 23, 87, 88, 108, 80, 120, 4, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 4,2 REFERENCES J. Earls & J. Rogers, 0.1361015212836455566..., Lulu Press, NY, 2006, p. 22. LINKS Amazon.com, 0.1361015212836455566...(Title of split novel) MATHEMATICA lpk[n_]:=Module[{k=1, c=10^n, p=Prime[n]}, While[!PrimeQ[k*c+p], k++]; k]; Array[ lpk, 80, 4] (* Harvey P. Dale, Sep 01 2020 *) CROSSREFS Sequence in context: A214592 A130437 A119813 * A245869 A184197 A173568 Adjacent sequences: A119983 A119984 A119985 * A119987 A119988 A119989 KEYWORD easy,nonn AUTHOR Jason Earls, Aug 03 2006 STATUS approved

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Last modified December 5 11:50 EST 2022. Contains 358586 sequences. (Running on oeis4.)