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A053710
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Prime-balanced factorials: factorials k! that are the mean of their 2 closest neighboring primes.
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5
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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k! = (p+q)/2; p = k! + d, q = k! - d, where p and q are the closest primes to k!.
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EXAMPLE
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For k=21, k!=51090942171709440000, d=31, and the closest primes to 21! are q = 21! - 31 = 51090942171709439969, p = 21! + 31 = 51090942171709440031.
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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The next two terms are 171! and 190!. - Jud McCranie, Jul 04 2000
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STATUS
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approved
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