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 A082700 Numbers k such that (15*10^(k-1) - 51)/9 is a plateau prime. 3
 5, 13, 17, 19, 37, 53, 73, 101, 6233, 24029, 40223, 66395 (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 Table of n, a(n) for n=1..12. Patrick De Geest, PDP Reference Table - 161. Makoto Kamada, Prime numbers of the form 166...661. Index entries for primes involving repunits. FORMULA a(n) = A056247(n+1) + 2. EXAMPLE k=13 -> (15*10^(13-1) - 51)/9 = 1666666666661. PROG (PARI) is(n)=ispseudoprime(2*(10^n-1)/3-5*(10^(n-1)+1)) || ispseudoprime(15*10^(n-1)-51)/9 \\ Charles R Greathouse IV, Feb 07 2013 CROSSREFS Cf. A056247, A068647, A082697-A082720. Sequence in context: A092218 A049092 A103666 * A212287 A174361 A226165 Adjacent sequences: A082697 A082698 A082699 * A082701 A082702 A082703 KEYWORD nonn,base,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 04 2014 STATUS approved

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Last modified September 28 03:41 EDT 2023. Contains 365715 sequences. (Running on oeis4.)