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A334038
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a(n) = Product_{p<=n, p prime} binomial(n,p).
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1
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1, 1, 1, 3, 24, 100, 1800, 15435, 702464, 13716864, 163296000, 1383574500, 109294479360, 3842829083808, 1159801183597056, 132320316074821875, 8213884352593920000, 327816138093181337600, 167079259535068179726336, 34044607357920579594754944
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OFFSET
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0,4
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LINKS
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EXAMPLE
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For n=2, p=2: a(n) = C(2,2) = 1.
For n=3, p=2,3: a(n) = C(3,2) * C(3,3) = 3.
For n=4, p=2,3: a(n) = C(4,2) * C(4,3) = 24.
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MAPLE
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a:= n-> mul(`if`(isprime(p), binomial(n, p), 1), p=2..n):
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PROG
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(PARI) a(n) = prod(k=1, n, if (isprime(k), binomial(n, k), 1)); \\ Michel Marcus, Apr 13 2020
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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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