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Arrangements with repetition

Combinatorics · Lesson

First biennium

Arrangements with repetition

A sequence has k ordered positions. If each position may choose again among the same n symbols, the product principle gives n^k.

Key idea
Formula matematica
Similar example
Formula matematica

Prerequisites: Fundamental counting principle

Goal: Count length-k sequences when each position may reuse any of n symbols: n^k.

Interactive laboratory

Explore before calculating

Change the data, observe how the number of cases changes, and use the lab to understand the counting structure you are using.

M-COMB-06

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Ask how many choices each position has and whether a symbol may appear again.

Guided

Completed exercises: 0/5 · Correct on first attempt: 0

How to reason

Each position starts again with all n choices: multiply n by itself k times.

Data / situation: A code has 5 positions and each position can use one of 6 symbols, with repetition.

Formula matematica
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What you need to know for Arrangements with repetition

ConceptStep separates what is required from what is recommended or useful as reinforcement. Only required prerequisites block your progress.

Current topic Strong skill Review due Needs reinforcement To be mastered Optional support

Relationships: solid line = required · dashed line = recommended · dotted line = reinforcement.

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