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C00002 00002	TO:   Richard Beigel
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TO:   Richard Beigel
FROM: Bob Floyd
RE:   proof by recursion

The proof by recursion theorem goes this way:

(1) Parameterless program determines its own index, n.
(2) Determine, using ≤k queries, whether phi↓n()↓. If yes, loop.
If no, print O (or something) and halt. Absurd.

			RWF

The idea is that of Rice's Theorem, which can probably be generalized
to suit your purposes.