YES Confluence Proof

Confluence Proof

by Hakusan

Input

The rewrite relation of the following TRS is considered.

a b
a f(a)
f(x) x

Proof

1 Compositional Parallel Critical Pair Systems

All parallel critical pairs of the TRS R are joinable by R. This can be seen as follows: The parallel critical pairs can be joined as follows. Here, ↔ is always chosen as an appropriate rewrite relation which is automatically inferred by the certifier.
The TRS C is chosen as:
a b
f(x) x
Consequently, PCPS(R,C) is included in the following TRS P where steps are used to show that certain pairs are C-convertible.

There are no rules.


Relative termination of P / R is proven as follows.

1.1 R is empty

There are no rules in the TRS R. Hence, R/S is relative terminating.


Confluence of C is proven as follows.

1.2 Compositional Parallel Critical Pair Systems

All parallel critical pairs of the TRS R are joinable by R. This can be seen as follows: The parallel critical pairs can be joined as follows. Here, ↔ is always chosen as an appropriate rewrite relation which is automatically inferred by the certifier.
The TRS C is chosen as:

There are no rules.

Consequently, PCPS(R,C) is included in the following TRS P where steps are used to show that certain pairs are C-convertible.

There are no rules.


Relative termination of P / R is proven as follows.

1.2.1 R is empty

There are no rules in the TRS R. Hence, R/S is relative terminating.


Confluence of C is proven as follows.

1.2.2 (Weakly) Orthogonal

Confluence is proven since the TRS is (weakly) orthogonal.

Tool configuration

Hakusan