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A173969
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Sums of three consecutive numbers each of which is the product of two distinct primes and each of which has no exponent greater than one for either of its two prime factors
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1
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102, 258, 282, 426, 606, 642, 654, 906, 1182, 1338, 1902, 2094, 2766, 3126, 3414, 3786, 4038, 4206, 4926, 5286, 5514, 5682, 5826, 5946, 6306, 6546, 6654, 6918, 7086, 7302, 7386, 7554, 7926, 8166, 8202, 9294, 10158, 10806, 11082, 11598, 11706, 11874
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OFFSET
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1,1
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COMMENTS
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Terms that included in A173968 but Not included in the current seq are: 366,2526,18726,220326,430926,637566,814326,..
The number of prime factors of each of the 3 consecutive numbers must be 2 even when counted with multiplicity. - Harvey P. Dale, Aug 14 2021
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LINKS
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MATHEMATICA
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f[n_]:=Last/@FactorInteger[n]=={1, 1}; lst={}; Do[If[f[n], If[f[n+1]&&f[n+2], AppendTo[lst, 3*n+3]]], {n, 8!}]; lst2=lst
Total[#]+Mean[#]&/@SequencePosition[Table[If[PrimeNu[n]==PrimeOmega[n]==2, 1, 0], {n, 4000}], {1, 1, 1}] (* Harvey P. Dale, Aug 14 2021 *)
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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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