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A043326
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Numbers k such that k is a product of two different primes and k-2 is prime.
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4
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15, 21, 33, 39, 55, 69, 85, 91, 111, 115, 129, 133, 141, 159, 183, 201, 213, 235, 253, 259, 265, 295, 309, 319, 339, 355, 381, 391, 403, 411, 445, 451, 469, 481, 489, 493, 501, 505, 511, 543, 559, 565, 573, 579, 589, 633, 649, 655, 679, 685
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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Select[Range[700], PrimeOmega[#]==PrimeNu[#]==2&&PrimeQ[#-2]&] (* Harvey P. Dale, Feb 01 2014 *)
Select[Prime[Range[200]]+2, PrimeOmega[#]==PrimeNu[#]==2&] (* Harvey P. Dale, Oct 13 2018 *)
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PROG
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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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