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A174383
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Product of two consecutive odd numbers n such that n+-2 are primes.
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2
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15, 99, 195, 399, 675, 1599, 12099, 15375, 21315, 42435, 62499, 106275, 115599, 122499, 190095, 193599, 220899, 401955, 470595, 495615, 846399, 1008015, 1110915, 1123599, 1263375, 1336335, 1552515, 1628175, 1674435, 1731855
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OFFSET
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1,1
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COMMENTS
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3*5 = 15+-2 -> primes, 9*11 = 99+-2 -> primes,..
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LINKS
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MATHEMATICA
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f[n_]:=n*(n+2); Select[Table[f[n], {n, 1, 7!, 2}], PrimeQ[ #-2]&&PrimeQ[ #+2]&]
Select[Times@@@Partition[Range[1, 2001, 2], 2, 1], And@@PrimeQ[#+{2, -2}]&] (* Harvey P. Dale, Dec 14 2012 *)
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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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