Sep 15, 2022 · Sep 15, 2022 · Sep 15, 2022 · Sep 15, 2022
diff --git a/Maths/LiouvilleFunction.js b/Maths/LiouvilleFunction.js
diff --git a/Maths/test/LiouvilleFunction.test.js b/Maths/test/LiouvilleFunction.test.js
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	/*
	* Author: Akshay Dubey (https://github.com/itsAkshayDubey)
	* Liouville Function: https://en.wikipedia.org/wiki/Liouville_function
	* For any positive integer n, define λ(n) as the sum of the primitive nth roots of unity.
	* It has values in {−1, 1} depending on the factorization of n into prime factors:
	* λ(n) = +1 if n positive integer with an even number of prime factors.
	* λ(n) = −1 if n positive integer with an odd number of prime factors.
	*/

	/**
	* @function liouvilleFunction
	* @description -> This method returns λ(n) of given number n
	* returns 1 when number has even number of prime factors
	* returns -1 when number has odd number of prime factors
	* @param {Integer} number
	* @returns {Integer} 1\|-1
	*/

	import { PrimeFactors } from './PrimeFactors.js'
	export const liouvilleFunction = (number) => {
	if (number <= 0) {
	throw new Error('Number must be greater than zero.')
	}
	return PrimeFactors(number).length % 2 === 0 ? 1 : -1
	}
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	import { liouvilleFunction } from '../LiouvilleFunction'

	const expectedValuesArray = [1, -1, -1, 1, -1, 1, -1, -1, 1, 1, -1, -1, -1, 1, 1, 1, -1, -1, -1, -1, 1, 1, -1, 1, 1, 1, -1, -1, -1, -1, -1, -1, 1, 1, 1, 1, -1, 1, 1, 1, -1, -1, -1, -1, -1, 1, -1, -1, 1, -1, 1, -1, -1, 1, 1, 1, 1, 1, -1, 1, -1, 1, -1, 1, 1, -1, -1, -1, 1, -1, -1, -1, -1, 1, -1, -1, 1, -1, -1, -1, 1, 1, -1, 1, 1, 1, 1, 1, -1, 1, 1, -1, 1, 1, 1, 1, -1, -1, -1, 1]

	describe('Testing liouville function', () => {
	for (let i = 1; i <= 100; i++) {
	it('Testing for number = ' + i + ', should return ' + expectedValuesArray[i], () => {
	expect(liouvilleFunction(i)).toBe(expectedValuesArray[i - 1])
	})
	}

	it('should throw error when supplied negative numbers', () => {
	expect(() => { liouvilleFunction(-1) }).toThrow(Error)
	})

	it('should throw error when supplied zero', () => {
	expect(() => { liouvilleFunction(0) }).toThrow(Error)
	})
	})