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A090090
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a(n) = prime(n)*prime(n+3).
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7
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14, 33, 65, 119, 209, 299, 493, 589, 851, 1189, 1333, 1739, 2173, 2537, 2867, 3551, 4189, 4453, 5293, 5893, 6497, 7663, 8383, 9167, 10379, 11009, 11639, 13589, 14279, 15481, 17653, 19519, 20687, 21823, 24287, 25217, 27161, 29177, 30227, 33043
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(5) = prime(5)*prime(8) = 11*19 = 209.
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MATHEMATICA
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First[#]*Last[#]&/@Partition[Prime[Range[200]], 4, 1] (* Harvey P. Dale, Dec 18 2011 *)
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PROG
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CROSSREFS
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Subset of the squarefree semiprimes, A006881.
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KEYWORD
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easy,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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