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A346581
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a(n) = (1/(7*n)) * Sum_{d|n} mu(n/d) * binomial(7*d,d).
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5
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1, 6, 63, 728, 9275, 124866, 1753073, 25365600, 375677595, 5667202850, 86775157139, 1345153422600, 21069043965983, 332927798516614, 5301031234076325, 84967018610221440, 1369846562874360886, 22199151535757655354, 361411377745122110421, 5908312923789590118600
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OFFSET
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1,2
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COMMENTS
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Inverse Euler transform of A002296.
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LINKS
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MATHEMATICA
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Table[(1/(7 n)) Sum[MoebiusMu[n/d] Binomial[7 d, d], {d, Divisors[n]}], {n, 20}]
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PROG
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(PARI) a(n) = sumdiv(n, d, moebius(n/d)*binomial(7*d, d))/(7*n); \\ Michel Marcus, Jul 24 2021
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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