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 A064777 Numbers k such that prime(k) - pi(k) is divisible by k. 0
 1, 2, 3, 18, 42, 95, 524, 273585, 1735537, 4406057, 4406063, 4406188, 4406196, 4406341, 4406539, 4406541, 28703894, 73694240, 73694281, 73694287, 73694360, 73694363, 73694410, 3287860772, 3287860773, 3287860880, 3287860889, 3287860895, 3287860897 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Table of n, a(n) for n=1..29. EXAMPLE k = 18 is a term: prime(18) = 61, pi(18) = 7, and (61-7)/18 = 54/18 = 3. MATHEMATICA Do[ If[ IntegerQ[ (Prime[n] - PrimePi[n])/n ], Print[n]], {n, 1, 6*10^7} ] Select[Range[5000000], Divisible[Prime[#]-PrimePi[#], #]&] (* Harvey P. Dale, Aug 12 2013 *) PROG (PARI) isok(k) = ((prime(k) - primepi(k)) % k) == 0; \\ Michel Marcus, Jun 15 2021 CROSSREFS Cf. A000040, A000720, A065139, A111181. Sequence in context: A073529 A134850 A163910 * A137784 A053195 A347429 Adjacent sequences: A064774 A064775 A064776 * A064778 A064779 A064780 KEYWORD nonn AUTHOR Labos Elemer and Robert G. Wilson v, Oct 18 2001 EXTENSIONS a(18)-a(23) from Donovan Johnson, Apr 23 2010 a(24)-a(29) from Donovan Johnson, Oct 17 2012 STATUS approved

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Last modified April 24 02:28 EDT 2024. Contains 371917 sequences. (Running on oeis4.)