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A076137
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Numbers n such that Omega(n)=Omega(n-1)+ Omega(n-2)+ Omega(n-3), where Omega(n) denotes the number of prime factors of n, counting multiplicity.
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3
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4, 32, 64, 96, 144, 180, 216, 224, 240, 360, 400, 432, 576, 600, 648, 672, 800, 972, 1008, 1040, 1088, 1104, 1188, 1232, 1260, 1344, 1400, 1404, 1408, 1456, 1500, 1584, 1620, 1624, 1680, 1700, 1764, 1800, 1840, 1880, 1904, 1920, 1980, 2000, 2040, 2064
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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LINKS
| Harvey P. Dale, Table of n, a(n) for n = 1..1000
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EXAMPLE
| a(3)=64 is a term because Omega(64)=6=Omega(63)+Omega(62)+Omega(61)=3+2+1=6
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MATHEMATICA
| l = {4}; Do[If[Omega[n] == Omega[n - 1] + Omega[n - 2] + Omega[n - 3], l = Append[l, n]], {n, 5, 5000}]; l
Transpose[Select[Partition[Range[2100], 4, 1], PrimeOmega[Last[#]] == Total[ PrimeOmega[Take[#, 3]]]&]][[4]] (* From Harvey P. Dale, Nov 29 2011 *)
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CROSSREFS
| Cf. A076136, A001222.
Sequence in context: A118901 A114076 A078092 * A138340 A113250 A012036
Adjacent sequences: A076134 A076135 A076136 * A076138 A076139 A076140
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KEYWORD
| nonn
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AUTHOR
| Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Oct 30 2002
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