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A111881
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Numerators of row sums of array of ratios A111879(n,k)/A111880(n,k).
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2
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1, 1, 29, 1, 103, 253, 1669, 181, 30791, 849, 452993, 41003, 94949, 421117, 18358463, 446801, 124184839, 30064511, 80932487, 19812817, 211524139, 333707681, 4757207109, 2557825027, 105920383973, 14417396537, 4649180818987
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OFFSET
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3,3
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COMMENTS
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The denominators are given in A069220(n), n>=3.
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LINKS
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FORMULA
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a(n)= numerator(sum(r(n, k), k=1..phi(n)-1), with phi(n):=A000010(n) (Euler's totient function) and the ratios r(n, k):=A111879(n, k)/A111880(n, k).
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EXAMPLE
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The ratios a(n)/A069220(n) are: 1/2, 1/3, 29/12, 1/5, 103/20, 253/105, 1669/280, 181/63, 30791/2520, 849/385, ... (see the W. Lang link under A111879.)
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CROSSREFS
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KEYWORD
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nonn,easy,frac
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AUTHOR
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STATUS
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approved
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