We consider universal computability of the LCTRS with only rule scheme Calc:

  Signature: eval :: Int -> Int -> Int -> o

  Rules: eval(x, y, z) -> eval(x + z, y + 1, z - 2) | x >= 0
         eval(x, y, z) -> eval(x + y, y - 2, z) | x >= 0

The system is accessible function passing by a sort ordering that equates all sorts.

We start by computing the initial DP problem D1 = (P1, R UNION R_?, f, c), where:

  P1. (1) eval#(x, y, z) => eval#(x + z, y + 1, z - 2) | x >= 0
      (2) eval#(x, y, z) => eval#(x + y, y - 2, z) | x >= 0

***** No progress could be made on DP problem D1 = (P1, R UNION R_?, f, c).