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A115168
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Even numbers n such that n-2 and n+2 have the same number of prime divisors with multiplicity.
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1
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8, 10, 12, 24, 36, 38, 58, 60, 68, 84, 86, 100, 102, 110, 112, 120, 134, 138, 144, 154, 172, 178, 184, 188, 204, 216, 230, 240, 244, 276, 284, 288, 300, 302, 320, 342, 346, 360, 368, 372, 374, 378, 384, 394, 396, 404, 408, 428, 432, 436, 440, 456, 466, 472
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OFFSET
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1,1
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LINKS
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MAPLE
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g(n) = forstep(x=4, n, 2, p1=bigomega(x-2); p2=bigomega(x+2); if(p1==p2, print(x", ")))
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MATHEMATICA
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Select[Range[4, 472, 2], PrimeOmega[# - 2] == PrimeOmega[# + 2] &] (* Amiram Eldar, Sep 23 2019 *)
2*Mean/@SequencePosition[Table[PrimeOmega[n], {n, 2, 500, 2}], {x_, _, x_}] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jun 20 2021 *)
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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