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Although not a TQG, the simplest and most familiar nondecomposable ternary function is the majority operation M over values a and b, defined by:

  1. M (a, a, a) = a
  2. M (a, a, b) = a
  3. M (a, b, a) = a
  4. M (a, b, b) = b
  5. M (b, a, a) = a
  6. M (b, a, b) = b
  7. M (b, b, a) = b
  8. M (b, b, b) = b

Suppose that there were a decomposition M (p, q, r) = F (p, G (q, r)). Then we would have:

  1. F (a, G (a, a)) = a
  2. F (a, G (a, b)) = a
  3. F (a, G (b, a)) = a
  4. F (a, G (b, b)) = b
  5. F (b, G (a, a)) = a
  6. F (b, G (a, b)) = b
  7. F (b, G (b, a)) = b
  8. F (b, G (b, b)) = b

Observe:

Thus G (a, a), G (a, b) and G (b, b) must be three distinct values. However there are only two values to choose from, namely a and b, so decomposition fails.