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 A167180 a(n) = pi(n) plus the number of nonprimes less than prime(n). 1
 1, 2, 4, 5, 9, 10, 14, 15, 18, 23, 25, 30, 34, 35, 38, 43, 49, 50, 56, 59, 60, 65, 69, 74, 81, 84, 85, 88, 90, 93, 107, 110, 115, 116, 125, 126, 132, 137, 140, 145, 151, 152, 162, 163, 166, 167, 179, 190, 193, 194, 197, 202, 204, 213, 218, 223, 228, 229, 235, 238, 240 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The number of primes less than n plus number of nonprimes less than n-th prime. LINKS FORMULA a(n)=A000720(n)+A014689(n). MAPLE Contribution from R. J. Mathar, May 21 2010: (Start) A000720 := proc(n) numtheory[pi](n) ; end proc: A014689 := proc(n) ithprime(n) -n ; end proc: A167180 := proc(n) A000720(n)+A014689(n) ; end proc: seq(A167180(n), n=1..120) ; (End) CROSSREFS Sequence in context: A024618 A089221 A113755 * A091271 A063985 A050052 Adjacent sequences:  A167177 A167178 A167179 * A167181 A167182 A167183 KEYWORD nonn AUTHOR Juri-Stepan Gerasimov, Oct 29 2009 EXTENSIONS Corrected (89 replaced by 88, 94 by 93, 127 by 126, 146 by 145 etc.) by R. J. Mathar, May 21 2010 STATUS approved

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