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 A038801 Number of primes less than 10n. 23
 4, 8, 10, 12, 15, 17, 19, 22, 24, 25, 29, 30, 31, 34, 35, 37, 39, 41, 42, 46, 46, 47, 50, 52, 53, 55, 57, 59, 61, 62, 63, 66, 66, 68, 70, 72, 73, 75, 77, 78, 80, 81, 82, 85, 87, 88, 91, 92, 93, 95, 97, 97, 99, 99, 101, 102, 104, 106, 107, 109, 111, 114, 114, 115, 118, 120 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS For almost all n, that is for a set of density 1, a(n) = a(n-1), and in all cases a(n) <= a(n-1) + 4. - Charles R Greathouse IV, Aug 27 2014 LINKS Robert G. Wilson v, Table of n, a(n) for n = 1..10000 Andrew R. Booker, The Nth Prime Page Thomas R. Nicely, Some Results of Computational Research in Prime Numbers Tomás Oliveira e Silva, Tables of values of pi(x) and of pi2(x) MATHEMATICA Table[ PrimePi[ n*10 ], {n, 1, 66}] (* Robert G. Wilson v *) PROG (PARI) a(n)=primepi(10*n) \\ Charles R Greathouse IV, Aug 27 2014 CROSSREFS Cf. A028505, A038812, A038813, A038814, A038815, A038816, A038817, A038818, A038819, A038820, A038821, A080122, A080123, A080124, A080125, A080126, A080127, A080128, A080129. Sequence in context: A175226 A057166 A230854 * A310977 A337813 A310978 Adjacent sequences:  A038798 A038799 A038800 * A038802 A038803 A038804 KEYWORD nonn AUTHOR EXTENSIONS Edited and corrected by Robert G. Wilson v, Jan 29 2003 STATUS approved

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Last modified April 13 15:23 EDT 2021. Contains 342936 sequences. (Running on oeis4.)