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A111087 Neither primes nor semiprimes. 3

%I

%S 1,8,12,16,18,20,24,27,28,30,32,36,40,42,44,45,48,50,52,54,56,60,63,

%T 64,66,68,70,72,75,76,78,80,81,84,88,90,92,96,98,99,100,102,104,105,

%U 108,110,112,114,116,117,120,124,125,126,128,130,132,135,136,138,140,144

%N Neither primes nor semiprimes.

%C 1 together with A033942.

%F a(n) = n + O(n log log n/log n). - _Charles R Greathouse IV_, Nov 13 2016

%t f[n_] := Plus @@ Last /@ FactorInteger[n]; Select[ Range[146], f[ # ] != 1 && f[ # ] != 2 &] (* _Robert G. Wilson v_ *)

%t Join[{1},Select[Range[200],PrimeOmega[#]>2&]] (* _Harvey P. Dale_, Mar 12 2018 *)

%o (PARI) is(n)=bigomega(n)>2 || n==1 \\ _Charles R Greathouse IV_, Nov 13 2016

%K easy,nonn

%O 1,2

%A Noelle Clou (keynews.tv(AT)skynet.be), Oct 12 2005

%E More terms from _Robert G. Wilson v_, Oct 12 2005

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Last modified March 25 10:19 EDT 2019. Contains 321470 sequences. (Running on oeis4.)