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mathematical induction

Proving a statement true for every whole number by knocking over an infinite line of dominoes.

The technique of mathematical induction shows a statement P(n) holds for every whole number n starting at some base case by two steps — a base case, showing P(n_0) is true, and an inductive step, showing that whenever P(k) is true, P(k+1) must be true too. Together they guarantee P(n) for every n \geq n_0, the way one falling domino guarantees every domino after it falls.

Examples

  • Proving 1+2+\cdots+n=\frac{n(n+1)}{2} for every n \geq 1 is a standard induction proof.

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