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A115168 Even numbers n such that n-2 and n+2 have the same number of prime divisors with multiplicity. 1

%I

%S 8,10,12,24,36,38,58,60,68,84,86,100,102,110,112,120,134,138,144,154,

%T 172,178,184,188,204,216,230,240,244,276,284,288,300,302,320,342,346,

%U 360,368,372,374,378,384,394,396,404,408,428,432,436,440,456,466,472

%N Even numbers n such that n-2 and n+2 have the same number of prime divisors with multiplicity.

%H Amiram Eldar, <a href="/A115168/b115168.txt">Table of n, a(n) for n = 1..10000</a>

%p g(n) = forstep(x=4,n,2,p1=bigomega(x-2);p2=bigomega(x+2);if(p1==p2,print(x",")))

%t Select[Range[4, 472, 2], PrimeOmega[# - 2] == PrimeOmega[# + 2] &] (* _Amiram Eldar_, Sep 23 2019 *)

%t 2*Mean/@SequencePosition[Table[PrimeOmega[n],{n,2,500,2}],{x_,_,x_}] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jun 20 2021 *)

%K easy,nonn

%O 1,1

%A _Cino Hilliard_, Mar 03 2006

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Last modified August 10 09:56 EDT 2022. Contains 356039 sequences. (Running on oeis4.)