A141098 Even numbers not representable as the sum of two coprime composite numbers.
2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 36, 38, 40, 42, 48, 50, 54, 56, 60, 66, 70, 72, 78, 80, 84, 90, 96, 108, 110, 120, 126, 132, 138, 140, 150, 180, 210
Offset: 1
Programs
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Mathematica
t = Table[Length[Select[Range[2, n/2], ! PrimeQ[#] && ! PrimeQ[n - #] && GCD[#, n - #] == 1 &]], {n, 2, 2000, 2}]; Flatten[2*Position[t, 0]] (* T. D. Noe, Dec 05 2013 *)
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