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    • Recursion-and-induction

    R-and-i-induction-principle

    Recursion and Induction: The Induction Principle

    The Induction Principle allows one to derive an arbitrary formula, ψ, from

    • Base Case : (implies (and (not q_1) … (not q_k)) ψ), and

    • Induction Step(s) : For each 1≤i≤k,
      (implies (and q_i ψ/σ_{i,1} … ψ/σ_{i,h_i})
               ψ),

    provided that for terms m, q_1,...q_k, and substitutions σ_{i,j}  (1≤i≤k, 1≤j≤h_i), the following are theorems:

    • Ordinal Conjecture : (o-p m), and

    • Measure Conjecture(s) : For each 1≤i≤k and 1≤j≤h_i,
      (implies q_i (o< m/σ_{i,j}  m)).

    Next: Relations Between Recursion and Induction (or Table of Contents)