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A111087 Neither primes nor semiprimes. 3
1, 8, 12, 16, 18, 20, 24, 27, 28, 30, 32, 36, 40, 42, 44, 45, 48, 50, 52, 54, 56, 60, 63, 64, 66, 68, 70, 72, 75, 76, 78, 80, 81, 84, 88, 90, 92, 96, 98, 99, 100, 102, 104, 105, 108, 110, 112, 114, 116, 117, 120, 124, 125, 126, 128, 130, 132, 135, 136, 138, 140, 144 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

1 together with A033942.

LINKS

Table of n, a(n) for n=1..62.

FORMULA

a(n) = n + O(n log log n/log n). - Charles R Greathouse IV, Nov 13 2016

MATHEMATICA

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

Join[{1}, Select[Range[200], PrimeOmega[#]>2&]] (* Harvey P. Dale, Mar 12 2018 *)

PROG

(PARI) is(n)=bigomega(n)>2 || n==1 \\ Charles R Greathouse IV, Nov 13 2016

CROSSREFS

Sequence in context: A160258 A071280 A033942 * A166083 A091375 A282671

Adjacent sequences:  A111084 A111085 A111086 * A111088 A111089 A111090

KEYWORD

easy,nonn

AUTHOR

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

EXTENSIONS

More terms from Robert G. Wilson v, Oct 12 2005

STATUS

approved

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Last modified February 16 21:05 EST 2019. Contains 320191 sequences. (Running on oeis4.)