# Questions tagged [math]

The challenge involves mathematics in some central way. Also consider using more specific tags, listed in the tag wiki info.

608 questions
Filter by
Sorted by
Tagged with
954 views

### Factor a polynomial over a finite field or the integers

Without using any built-in factoring/polynomial functions, factor a polynomial completely into irreducibles over the integers or a finite field. Input Your program/function will receive some prime (or ...
740 views

### Round to n Sig Figs

Challenge Given a number x and a number n, round number x to ...
2k views

### Length of String Using Set Theory

From Wikipedia Set-theoretic definition of natural numbers The set N of natural numbers is defined as the smallest set containing 0 and closed under the successor function S defined by S(n) = n ∪ ...
873 views

### Dames, do some math!

The order of operations, PEMDAS, is a basic rule in mathematics telling us which order operations should be performed: "Parentheses, Exponents, Multiplication and Division, and Addition and ...
2k views

### What is the average of n, the closest prime to n, the square of n and the closest Fibonacci number to n?

This is a math problem which takes quite many things into question, making it rather challenging, and as you might have guessed, it's a code golf, so it should be as short as possible as well. The ...
2k views

### Generate a number by using a given list of numbers and arithmetic operators

You are given a list of numbers L = [17, 5, 9, 17, 59, 14], a bag of operators O = {+:7, -:3, *:5, /:1} and a number ...
18k views

### Hyperprogramming: N+N, N×N, N^N all in one

Write a program that takes in a number N from 1 to 9 inclusive. In its native form your program should output N+N. E.g. output 2 if N is ...
9k views

### Yo boy, must it sum

Every positive integer can be expressed as the sum of at most three palindromic positive integers in any base b≥5.   Cilleruelo et al., 2017 A positive integer is palindromic in a given base if ...
8k views

### The vanilla factorial challenge

Task Given a non-negative integer $n$, evaluate the factorial $n!$. The factorial is defined as follows: $$n!=\begin{cases}1 & n=0\\n\times(n-1)!&n>0\end{cases}$$ Rules All default I/...
5k views

### Product over a range

Your task is simple: given two integers $a$ and $b$, output $\Pi[a,b]$; that is, the product of the range between $a$ and $b$. You may take $a$ and $b$ in any reasonable format, whether ...
8k views

### Is this number a factorial?

The Task Given a natural number as input, your task is to output a truthy or falsey value based on whether the input is a factorial of any natural number. You can assume that the input number will ...
6k views

### Construct the Identity Matrix

The challenge is very simple. Given an integer input n, output the n x n identity matrix. The identity matrix is one that has <...
14k views

### Count sum of all digits

This challenge is to write a program or script which counts the sum of all digits within the integers from 1 up to and including a given number. Input, one positive integer. Output, the sum of digits ...
9k views

### Shift right by half a bit

The challenge is to implement a program or function (subsequently referred to as "program") that takes a nonnegative integer $n$ as input and returns $n\over\sqrt{2}$ (the input divided by the ...
4k views

### Sums of Consecutive Integers

Before anyone says anything, similar and similar. But this is not a dupe. Some positive integers can be written as the sum of at least two consecutive positive integers. For example, ...
2k views

### Print, Increment, Decrement, Alias - Interpret Prindeal

Prindeal (pronounced prin-dee-al) is a new esoteric programming language that only has four commands: print, increment, decrement, and alias. Despite its minimalism, complex mathematical operations ...
5k views

### Index of a multidimensional array

Lower level languages, such as C and C++ actually have no concept of multidimensional arrays. (Other than vectors and dynamic arrays) When you create a multidimensional array with ...
5k views

### How Many Rectangles in the Grid?

Well, although this challenge turned out to be a huge success, it also turned out to be very trivial to solve. Therefore, for those of looking for more of a challenge, I created a sequel to this ...
5k views

### Factorial digit sum

The challenge is to calculate the digit sum of the factorial of a number. Example Input: 10 Output: 27 10! = 10 × 9 × ... × 3 × 2 × 1 = 3628800, and the sum of ...
7k views

### Minimum excluded number

This is intended to be an easy, bite-size code-golf. The mex (minimal excluded number) of a finite collection of numbers is the smallest non-negative integer ...
3k views

### Convert a number to Hexadecimal

Challenge Here's a simple one. Write a function or program when given a number in base 10 as input, it will return or print that number's value in Hexadecimal. Examples ...
3k views

### Closest fraction

Task: Your program is given a proper, positive simple fraction in the format <numerator>/<denominator>. For this input, it must find two fractions. A ...
4k views

### Basic Calculator

You must write a program to evaluate a string that would be entered into a calculator. The program must accept input and output the correct answer. For languages that do not have standard input/...
3k views

### Find the Squarish Root

Write code that when given a positive number $x$ as input, outputs the largest positive divisor of $x$ less than or equal to the square root of $x$. In other words find the largest $n > 0$ ...
8k views

### Find the Pisano Period

The Fibonacci sequence is a well know sequence in which each entry is the sum of the previous two and the first two entries are 1. If we take the modulo of each term by a constant the sequence will ...
4k views

### Female and Male Sequences

This question is probably harder than all of those "generate a sequence of numbers" tasks, because this requires TWO sequences working in unison. Really looking forward to the answers! In his book "...
1k views

### Calculate the n-th iterate of a polynomial for a specific value; fⁿ(x)

Given a polynomial function f (e.g. as a list p of real coefficients in ascending or descending order), a non-negative integer n, and a real value x, return:    f n(x) i.e. the value of f (f (f (…f (x)...
2k views

### Symbolic Differentiation of Polynomials

Symbolic Differentiation 1: Gone Coefishin' Task Write a program that takes in a polynomial in x from stdin (1 < deg(p) < 128) and differentiates it. The input polynomial will be a string of ...
2k views

### Generate n digits of Gijswijt's sequence

Introduction Gijswijt's sequence (A090822) is famously really, REALLY slow. To illustrate: The first 3 appears in the 9th term (alright). The first 4 appears in the 220th term (a long way away, but ...
2k views

### Partial Sum of Harmonic Sequence!

Definition In Mathematics, Harmonic Sequence refers to a sequence where $$a_n = \frac 1 n$$ i.e. the $n_{th}$ term of the sequence equals the reciprocal of $n$. Introduction In this challenge, ...
2k views

### How many partitions do I have?

The partition number of a positive integer is defined as the number of ways it can be expressed as a sum of positive integers. In other words, the number of integer partitions it has. For example, the ... 3k views

### Roman numeral converter function

Create the shortest function to convert a string of Roman numerals to an integer. The rules for each letter can be found at the Wikipedia page. Letters above 1,000 will have parentheses placed ...
960 views

### Become the Hydra Slayer

You are the best and most famous hero of the area. Lately there have been rumors that a Hydra has been hanging out in a nearby ravine. Being the brave and virtuous hero that you are you figure you'll ...
649 views

### Perfect powers in more than one way?

Challenge Your task is to write a program or function which, given a positive integer $N$, finds all positive integers less than or equal to $N$ that can be expressed as a perfect power in more ...
2k views

### Convert from Infix Notation to Prefix Notation

Given an arithmetic expression, which can include parentheses (()), exponents (^), division (...
1k views

### Operations with Lists

Inspired by this question. Given a list containing numbers, print: The sum and product of the numbers in the list The average and median The differences between each term in the list (e.g. ...
954 views

### Permutation Numbering

The Challenge For a given set of n integers, write a program which will output its lexicographic index. The Rules The input must only be a set of unique non-negative integers separated by spaces. ...
4k views

### Convert radicals to mixed & entire radicals and to real numbers [closed]

Challenge The goal of this challenge is to take a radical and convert it to a reduced and entire radical, and a real number. You do not have to convert it to all 3, however, you will get bonus points ...
932 views

### Find the simplest value between two values

Goal Your goal is to find the simplest value in an open interval. In other words, given two values a,b with a<b, output the ...
1k views

### Generate all 4-perfect numbers

Your program or function should output all the 36 4-perfect numbers in increasing order separated by newlines. An n positive integer is a ...
767 views

### Draw diagonal positions of me squared

Based on the interpretation user @ThePirateBay made from the first version of my own challenge Output diagonal positions of me squared now I challenge you to make ASCII art that draws diagonal lines ...
41k views

### Programming Languages Through The Years

In this challenge, users will take turns completeing three fairly simple coding tasks in programming languages that are allowed to be progressively older. The first answer must use a programming ...
41k views

### Hard code golf: Regex for divisibility by 7

Matthias Goergens has a 25,604-character (down from the original 63,993-character) regex to match numbers divisible by 7, but that includes a lot of fluff: redundant parentheses, distribution (...
15k views

### Calculate the number of primes up to n

π(n) is the number of primes less than or equal to n. Input: a natural number, n. Output: π(n). Scoring: This is a fastest-code challenge. Score will be the sum of times for the score cases. I ...
18k views

### 9 Hole Challenge [closed]

The 9 Hole Challenge 9 code golfing challenges of varying difficulty. Penalties for using the same language more than once. The question will be updated with pars, hole champions and trophy winners....
4k views

### Help me with differential calculus!

I love programming and know every language, but I suck at math. Unfortunately, my school requires that computers students must take a year of calculus. There's a test next week, and I don't know any ...
7k views

### Multiplicative persistence

Multiplicative Persistence Multiply all the digits in a number Repeat until you have a single digit left As explained by Numberphile: Numberphile "What's special about 277777788888899?" ...
4k views

### Too Fast, Too Fourier: FFT Code Golf

Implement the Fast Fourier Transform in the fewest possible characters. Rules: Shortest solution wins It can be assumed that the input is a 1D array whose length is a power of two. You may use the ...
The Ackermann function is notable for being the one of the simplest examples of a total, computable function that isn't primitive recursive. We will use the definition of $A(m,n)$ taking in two ...
A positive integer $k$ is a Loeschian number if $k$ can be expressed as $i^2 + j^2 + i\times j$ for $i$, $j$ integers. For example, the first positive Loeschian numbers are: $1$ (\\$i=1, ...