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A212792
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Product of all primes in the interval ((n+1)/2,n].
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2
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1, 2, 3, 3, 5, 5, 35, 35, 7, 7, 77, 77, 143, 143, 143, 143, 2431, 2431, 46189, 46189, 4199, 4199, 96577, 96577, 7429, 7429, 7429, 7429, 215441, 215441, 6678671, 6678671, 392863, 392863, 392863, 392863, 765049, 765049, 765049, 765049, 31367009, 31367009, 1348781387
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OFFSET
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1,2
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COMMENTS
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The case n=1 is special and defined conventionally.
Notice that the interval is semiopen; a prime p is included in the product if (n+1)<2p<=2n.
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LINKS
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EXAMPLE
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a(13) = product of all primes in (7,13] = 11*13 = 143.
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PROG
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(PARI) {p2(n) = result=1; forprime(p=1+floor((n+1)\2), n, result=result*p); }
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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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