- ... recursively.
^{1}
- When you consider the
integers as such a structure, where all numbers are defined by
recursively adding one to itself, you get straight induction
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- ... contrapositive.
^{2}
- In the
general form of proof by contradiction, you assume both not
*B* and
*A*, and work towards a contradiction somewhere in the middle. In
proof by contrapositive, the contradiction is always on the *A* side.
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