Exercise:

EXISTS x(I) R(OI) x AND FORALL y(I) [R y IMPLIES EXISTS z(I) Q(OII) y z] AND FORALL x FORALL y [Q x y IMPLIES Q x x] IMPLIES EXISTS x EXISTS y .Q x y AND R y

You may not use ADVICE, but all other rules and commands are allowed.

Only book theorems may be ASSERTed as lemmas without proof.

For a complete list of book theorems, type PROBLEMS.

No more help available. Sorry.

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