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A172366
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Number of partitions of prime(n) into the sum of two semiprimes.
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1
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0, 0, 0, 0, 0, 1, 0, 2, 1, 2, 3, 2, 2, 4, 4, 3, 5, 6, 4, 6, 5, 5, 7, 4, 7, 6, 7, 7, 5, 5, 8, 8, 8, 8, 9, 10, 9, 7, 13, 10, 10, 11, 13, 10, 10, 10, 11, 15, 18, 13, 10, 13, 14, 16, 12, 18, 12, 15, 12, 11
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OFFSET
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1,8
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LINKS
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FORMULA
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EXAMPLE
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a(8)=2 because prime(8)=19=4(semiprime)+15(semiprime)=9(semiprime)+10(semiprime).
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MATHEMATICA
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Table[Total[If[PrimeOmega[#]=={2, 2}, 1, 0]&/@Table[{x-n, n}, {n, x/2}]], {x, Prime[ Range[60]]}] (* Harvey P. Dale, Dec 21 2015 *)
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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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