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A308943
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a(n) = Product_{d|n} binomial(n,d).
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2
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1, 2, 3, 24, 5, 1800, 7, 15680, 756, 113400, 11, 79693891200, 13, 4372368, 20495475, 44972928000, 17, 2028339316523520, 19, 52737518268864000, 3247700400, 3585005424, 23, 38135556819759802035135799296, 1328250, 87885070000, 370142004375, 10293527616645873600000, 29
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OFFSET
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1,2
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LINKS
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FORMULA
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a(n) = Product_{k=1..n} binomial(n,gcd(n,k))^(1/phi(n/gcd(n,k))) = Product_{k=1..n} binomial(n,n/gcd(n,k))^(1/phi(n/gcd(n,k))) where phi = A000010. - Richard L. Ollerton, Nov 08 2021
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MATHEMATICA
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Table[Product[Binomial[n, d], {d, Divisors[n]}], {n, 1, 29}]
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PROG
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(PARI) a(n) = my(p=1); fordiv(n, d, p *= binomial(n, d)); p; \\ Michel Marcus, Jul 02 2019
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CROSSREFS
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Cf. A000010 (comments on product formulas).
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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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