Fibonacci Number(s)

Overview

Multiple utilities are offered for working with the Fibonacci sequence:

• Generate full sequences (iteratively or recursively with memoization)
• Fetch a specific Fibonacci term by index
• Lazily iterate using a generator
• Supports aliases for convenient use

All inputs are coerced and validated using Number().

getFibonacciSeries

Generates the first limit Fibonacci numbers iteratively.

Function Signature

function getFibonacciSeries(limit: Numeric): number[]

Parameters

• limit (Numeric): Number of Fibonacci numbers to generate.

Returns

• number[]: An array of Fibonacci numbers from index 0 to limit - 1. If the input is invalid or non-positive, an empty array is returned.

Example

Aliases

• getFibonacci
• getFibonacciNumbers

getFibonacciSeriesMemo

Generates the first limit Fibonacci numbers using recursion with memoization.

Function Signature

function getFibonacciSeriesMemo(limit: Numeric): number[]

Parameters

• limit (Numeric): Number of Fibonacci numbers to generate.

Returns

• number[]: An array of Fibonacci numbers from index 0 to limit - 1. Invalid input returns an empty array.

Example

Aliases

• getMemoizedFibonacci
• getMemoizedFibonacciSeries

fibonacciGenerator

A lazy generator that yields Fibonacci numbers up to a given limit.

Function Signature

function* fibonacciGenerator(
  limit: Numeric,
  onYield?: (value: number, index: number) => void
): Generator<number, void, void>

Parameters

• limit (Numeric): Number of Fibonacci values to yield.
• onYield (optional): Callback called on each yield with (value, index).

Returns

• Generator<number, void, void>: A generator that yields Fibonacci numbers one by one up to the specified limit.

Examples

Aliases

• generateFibonacci

getNthFibonacci

Returns the Fibonacci number at the specified term index.

Function Signature

function getNthFibonacci(index: Numeric): number

Parameters

• index (Numeric): Index (0-based) of the Fibonacci term to retrieve.

Returns

• number: The Fibonacci number at the given index.

Example

Summary of Aliases

Notes & Limitations

• The recursive memoized version getFibonacciSeriesMemo() is not tail-call optimized and can hit stack limits on very high values.
• getNthFibonacci() uses an efficient iterative approach.
• Floating-point limits apply at high index values (n > 70).