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A301600
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a(n) = Primorial(n) / Product_{k prime<n} k.
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0
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1, 2, 6, 15, 35, 385, 1001, 17017, 46189, 1062347, 30808063, 955049953, 3212440751, 131710070791, 435656388001, 20475850236047, 1085220062510491, 64027983688118969, 229747470880897477, 15393080549020130959, 57521511525285752531, 4199070341345859934763, 331726556966322934846277
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OFFSET
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0,2
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COMMENTS
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Sum_{n>=0} 1/a(n) = 1.765582555581609270...
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LINKS
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FORMULA
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EXAMPLE
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a(5) = 2*3*5*7*11 / 2*3 = 385.
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PROG
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(PARI) a(n) = prod(k=1, n, prime(k))/prod(k=1, n-1, if (isprime(k), k, 1)); \\ Michel Marcus, Mar 26 2018
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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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