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Subsumption of Induction Candidates in App Example

Subsumption of Induction Candidates in App Example

After collecting induction suggestions from these three terms

(app a b) 
 
(app b c) 
 
(app a (app b c)) 

the system notices that the first and last suggest the same decomposition of a: case split on whether a is empty (i.e., (endp a)), and in the case where it is not empty, recursively process (cdr a). So we are left with two ideas about how to induct:

Decompose a as we would to unwind (app a b).

Decompose b as we would to unwind (app b c).