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A167180
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a(n) = pi(n) plus the number of nonprimes less than prime(n).
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1
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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
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OFFSET
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1,2
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COMMENTS
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The number of primes less than n plus the number of nonprimes less than the n-th prime.
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LINKS
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FORMULA
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MAPLE
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A000720 := proc(n) numtheory[pi](n) ; end proc:
A014689 := proc(n) ithprime(n) -n ; end proc:
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MATHEMATICA
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Table[PrimePi[n] + Prime[n] - n , {n, 1, 20}] (* G. C. Greubel, Jun 04 2016 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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Corrected (89 replaced with 88, 94 with 93, 127 with 126, 146 with 145, etc.) by R. J. Mathar, May 21 2010
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STATUS
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approved
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