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A053708
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Nearest prime to n! (but not equal to n!).
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0
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2, 3, 5, 23, 113, 719, 5039, 40343, 362867, 3628789, 39916801, 479001599, 6227020777, 87178291199, 1307674368043, 20922789888023, 355687428096031, 6402373705728037, 121645100408832089, 2432902008176640029
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OFFSET
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1,1
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COMMENTS
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If n! is the average of its closest prime neighbors then the smaller prime is to be chosen (as in A051701).
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LINKS
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EXAMPLE
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For 8!=40320 the closest upper and lower primes are 40289 and 40343 with d=31 and d=23, so 40343 is closer to 8! than the lower neighbor.
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MATHEMATICA
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f[n_]:=Module[{nf=n!, s, l}, s=NextPrime[nf, -1]; l=NextPrime[nf]; If[nf-s>l-nf, l, s]]
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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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STATUS
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approved
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