Alger logo
𝔸𝕝𝕘𝕖𝕣
About

Perfect Numbers

namespace Algorithms.Math

module PerfectNumbers =
    /// Check if a number is perfect. Time complexity: O(√n)
    let isPerfect n =
        match n with
        | n when n <= 0 -> false
        | n ->
            { 1 .. n - 1 }
            |> Seq.takeWhile (fun i -> i * i <= n)
            |> Seq.filter ((%) n >> (=) 0)
            |> Seq.fold (fun acc i -> acc + i + n / i) 0
            |> (=) (2 * n)
Algerlogo

© Alger 2022

About us

We are a group of programmers helping each other build new things, whether it be writing complex encryption programs, or simple ciphers. Our goal is to work together to document and model beautiful, helpful and interesting algorithms using code. We are an open-source community - anyone can contribute. We check each other's work, communicate and collaborate to solve problems. We strive to be welcoming, respectful, yet make sure that our code follows the latest programming guidelines.