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n such that Omega(n-1) < Omega(n) < Omega(n+1), where Omega(m) = the number of prime factors of m, counting multiplicity.
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%I #11 Oct 29 2018 02:26:08

%S 62,63,74,188,194,195,207,242,255,275,278,279,314,363,374,398,399,404,

%T 422,423,455,458,483,494,495,524,539,614,615,662,663,674,692,728,734,

%U 735,747,758,759,764,782,783,854,867,890,927,935,975,998,999

%N n such that Omega(n-1) < Omega(n) < Omega(n+1), where Omega(m) = the number of prime factors of m, counting multiplicity.

%H Robert Israel, <a href="/A076764/b076764.txt">Table of n, a(n) for n = 1..10000</a>

%e Omega(61) = 1 < Omega(62) = 2 < Omega(63) = 3, so 62 is a 1-apex of Omega.

%p Res:= NULL: a:= numtheory:-bigomega(1): b:= numtheory:-bigomega(2):

%p for n from 3 to 1001 do

%p c:= numtheory:-bigomega(n);

%p if a < b and b < c then Res:= Res, n-1 fi;

%p a:= b; b:= c;

%p od:

%p Res; # _Robert Israel_, Oct 28 2018

%t Select[Range[3, 10^3], Omega[ # - 1] < Omega[ # ] < Omega[ # + 1] &]

%t Flatten[Position[Partition[PrimeOmega[Range[1000]],3,1],_?(Min[ Differences[ #]]>0&),{1},Heads->False]]+1 (* _Harvey P. Dale_, Nov 28 2015 *)

%Y Cf. A001222, A097619.

%K nonn

%O 1,1

%A _Joseph L. Pe_, Nov 13 2002

%E Edited by _Robert Israel_, Oct 28 2018