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A135667
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Least k such that k!! > prime(1)*prime(2)*...*prime(n) where prime(n) is the n-th prime.
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2
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3, 4, 6, 8, 10, 12, 14, 16, 19, 21, 23, 25, 28, 30, 32, 34, 37, 39, 41, 43, 46, 48, 50, 52, 55, 57, 59, 62, 64, 66, 68, 71, 73, 75, 78, 80, 82, 84, 87, 89, 91, 94, 96, 98, 101, 103, 105, 108, 110, 112, 114, 117, 119, 121, 124, 126, 128, 131, 133, 135, 138
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OFFSET
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1,1
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LINKS
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PROG
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(PARI) dbf(n) = prod(i = 0, floor((n-1)/2), n - 2*i );
a(n) = pr = prod(i = 1, n, prime(i)); k = 1; while(dbf(k) <= pr, k++); k; \\ Michel Marcus, Oct 13 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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EXTENSIONS
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STATUS
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approved
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