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A102614
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Denominators of the reduced fractions of the ratios of the number of primes less than n over the number of composites less than n.
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0
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1, 1, 1, 1, 2, 1, 3, 1, 5, 3, 6, 7, 7, 4, 3, 5, 10, 11, 11, 3, 13, 7, 14, 5, 16, 17, 2, 19, 19, 2, 20, 21, 2, 23, 24, 25, 25, 13, 9, 7, 28, 29, 29, 15, 31, 16, 32, 11, 34, 7, 12, 37, 37, 19, 39, 5, 41, 21, 42, 43, 43, 22, 5, 23, 47, 8, 48, 49, 50, 51, 51, 13, 52, 53, 18, 55, 8, 19, 57, 29
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OFFSET
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1,5
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LINKS
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FORMULA
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pi(n) is the number of primes <= n. Number of composites <= n = n - pi(n).
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MATHEMATICA
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frac[n_]:=Module[{ps=PrimePi[n]}, ps/(n-ps)]; Denominator/@Array[frac, 90] (* Harvey P. Dale, May 19 2011 *)
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PROG
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(PARI) pixovcmpx(n) = for(x=1, n, print1(denominator(pi(x)/(x-pi(x)))", ")) pi(n) = \Number of primes less than or equal to n. { local(c, x); c=0; forprime(x=1, n, c++); return(c) }
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CROSSREFS
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KEYWORD
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frac,nonn
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AUTHOR
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STATUS
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approved
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