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A092435
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Prime factorials divided by their corresponding primorials.
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7
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1, 1, 4, 24, 17280, 207360, 696729600, 12541132800, 115880067072000, 1366643159020339200000, 40999294770610176000000, 1854768736099424576471040000000, 109950690675973888893203251200000000
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OFFSET
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1,3
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LINKS
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FORMULA
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a(n) = Product_{k=1..n} prime(k)^(A085604(prime(n),k)-1).
a(n) = Product_{k=1..prime(n)} k^A066247(k). (End)
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EXAMPLE
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E.g., 2 factorial divided by 2 primorial is 1; 3 factorial is 6, divided by 3 primorial (3*2=6) is also 1; 5 factorial is 120, divided by 5 primorial (5*3*2=30) is 4 and so forth.
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MATHEMATICA
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Table[ Prime[n]! / Times @@ Prime[ Range[ n]], {n, 13}] (* Robert G. Wilson v, Mar 25 2004 *)
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PROG
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(PARI) a(n)=prime(n)!/prod(i=1, n, prime(i)) \\ Ralf Stephan, Dec 21 2013
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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Don Willard (dwillard(AT)prairie.cc.il.us), Mar 23 2004
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EXTENSIONS
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STATUS
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approved
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