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A346578
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a(n) = (1/(4*n)) * Sum_{d|n} mu(n/d) * binomial(4*d,d).
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5
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1, 3, 18, 112, 775, 5598, 42287, 328640, 2615085, 21191125, 174303162, 1451424960, 12211799223, 103655906781, 886568152950, 7633233227520, 66105170315083, 575445689879247, 5032380942945321, 44191451767056400, 389514699012969936, 3444925385161998518, 30561576846316109863
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OFFSET
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1,2
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COMMENTS
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Inverse Euler transform of A002293.
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LINKS
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MATHEMATICA
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Table[(1/(4 n)) Sum[MoebiusMu[n/d] Binomial[4 d, d], {d, Divisors[n]}], {n, 23}]
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PROG
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(PARI) a(n) = sumdiv(n, d, moebius(n/d)*binomial(4*d, d))/(4*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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