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A143993
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Composite numbers n such that the sum of prime factors of n (counted with multiplicity) terminates n as a substring.
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2
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4, 18, 220, 230, 246, 366, 444, 624, 1166, 1323, 1462, 1530, 1992, 2230, 2406, 2625, 2730, 3024, 3125, 3182, 3286, 3484, 3606, 3760, 4220, 5733, 6372, 6435, 7592, 8658, 8856, 9585, 9747, 10143, 10850, 11232, 11655, 13176, 13230, 13275, 13760, 14792
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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a(9)=1166=2*11*53 and 2+11+53=66 and 1166 ends in 66.
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MATHEMATICA
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nssQ[n_]:=Module[{idn=IntegerDigits[n], ss=IntegerDigits[Total[ Flatten[ Table[#[[1]], {#[[2]]}]&/@FactorInteger[n]]]]}, Take[idn, -Length[ss]] == ss]; Select[Range[2, 15000], !PrimeQ[#]&&nssQ[#]&] (* Harvey P. Dale, Sep 03 2012 *)
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CROSSREFS
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KEYWORD
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base,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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