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 A108511 a(n) is the smallest number m such that prime(m) = n*m - 1, or 0 if no such m exists. 1
 0, 2, 1, 0, 70, 182, 440, 1053, 0, 6458, 0, 40087, 0, 251737, 637320, 1617173, 4124466, 10553445, 27067100, 69709705, 179992910, 465769811, 0, 3140421738, 8179002128, 21338685403, 0, 0, 382465573528, 0, 0, 6935812012545, 18262325820324, 0, 0, 335276334036937 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS A108512(n) gives number of solutions of the equation prime(x) = n*x - 1. LINKS Table of n, a(n) for n=1..36. EXAMPLE a(26) = 21338685403 because prime(21338685403) = 26*21338685403 - 1 and 21338685403 is the smallest (only) number m with this property. CROSSREFS Cf. A108512, A108514. Sequence in context: A051652 A077019 A139037 * A261160 A270668 A196272 Adjacent sequences: A108508 A108509 A108510 * A108512 A108513 A108514 KEYWORD nonn AUTHOR Farideh Firoozbakht, Jun 12 2005 EXTENSIONS a(29)-a(33) from Donovan Johnson, Nov 15 2009 a(34)-a(36) from Jinyuan Wang, Aug 09 2021 STATUS approved

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Last modified February 27 16:21 EST 2024. Contains 370378 sequences. (Running on oeis4.)