Questions tagged [math]
The challenge involves mathematics in some central way. Also consider using more specific tags, listed in the tag wiki info.
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In between fractions
Given two positive integer fractions \$x\$ and \$y\$ such that \$x < y\$, give the fraction \$z\$ with the smallest positive integer denominator such that it is between \$x\$ and \$y\$.
For example ...
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Find the Lowest Allowable Integer Which is an Optimal Even-Harmonic of the Values in a List [closed]
PROBLEM
For a list of numbers, list: Find the lowest possible integer, x, which is optimally close to the whole number even-...
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Alternating sums of multidimensional arrays
Given a multidimensional array, find the recursive alternating sum. An alternating sum is simply the sum of an array, where every other item (starting with the second) is negated. For example, the ...
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ASCII-Art n'th Root
Challenge:
Given two integers \$a\$ and \$b\$, with lengths \$A=length(a), B=length(b)\$, output an ASCII-art of the \$a^{th}\$ root of \$b\$, including the answer rounded to \$A\$ amount of decimal ...
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Best performance on x/(y+z) + y/(x+z) + z/(x+y) = N
Consider the equation $$\frac x {y+z} + \frac y {x+z} + \frac z {x+y} = n$$ for positive integers \$x, y, z\$ and \$n \ge 4\$. Your code will receive \$n\$ as an input, and output three integers \$x, ...
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Sorting passengers on a plane
A few days ago I made a puzzle about moving people on an airplane. Now I am interested in the general version of this puzzle and the shortest code golf for it.
I will briefly summarise the puzzle here....
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Rounding a range
You have a line with two endpoints a and b (0 ≤ a < b) on a 1D space. When ...
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Collatz Encoding
The Collatz Conjecture
The famous Collatz Conjecture (which we will assume to be true for the challenge) defines a sequence for each natural number, and hypothesizes that every such sequence will ...
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Is this polynomial a square?
Given an integral polynomial \$p\$, determine if \$p\$ is a square of another integral polynomial.
An integral polynomial is a polynomial with only integers as coefficients.
For example, \$x^2+2x+1\$ ...
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Convert angle to clock time
Your task is to make a program or function that takes a nonnegative integer (or a different convenient format to represent it) that represents an angle measure in degrees from 0 to 180 (inclusive) as ...
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Find the weight of five apples
Problem
John bought 5 apples. You are given the weights of every group of four apples, and must then find the weights of the apples themselves.
For example, if all apples without the first one weigh ...
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Convert from variable-width Two's Complement to Integer
Take an input, and convert it from Two's Complement notation (binary where the first bit is negated, but the rest are taken as normal) into an integer (in a somewhat standard output form). Input can ...
- 1,250
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Randomly Rounding
Input a decimal number and round it to an integer, randomly rounding up or down with a probability based on its fractional part, so the expected value of the output equals to the input value.
If ...
- 28.6k
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Is it irrational?
Your task is to make a program that decides if a real number between 0 and 1 is irrational or not. As stated, this is obviously impossible, so instead we will use the following definition:
...
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Find the magic numbers to divide a number without division
An integer \$x\in[0,2^{32}-1]\$ divided by an integer \$d\in{[1,2^{31}]}\$ will produce an integral quotient \$q\$ and a remainder \$r\$, so that \$x=d\times q+r\$.
Any \$q\$, in fact, can be ...
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Random Point from a 2D Donut Distribution
A donut distribution (for lack of a better term) is a random distribution of points in a 2-dimensional plane, forming a donut-like shape. The distribution is defined by two parameters: the radius <...
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Can you draw this in one stroke?
Related | Related
Given an ASCII art with |, _, and , check if you can draw the art in one ...
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Find All Digitroot Cyclic Sequences With Length Greater Than One
Digital sum, DR, Digit root is the iterative process of summing digits of a number until you end up with a single digit root number: e.g. digit root of 12345 is 6 since 1 + 2 + 3 + 4 + 5 = 15 = 1+5. ...
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Coordinates for a Heronian tetrahedron
Did you know that Heronian Tetrahedra Are Lattice Tetrahedra? A Heronian tetrahedron is a tetrahedron where
the length of each edge is an integer,
the area of each face is an integer, and
the volume ...
- 8,097
18
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Find a factorial with n trailing zeros, quickly
Problem
A fact you may have noticed about factorials is that as \$n\$ gets larger \$n!\$ will have an increasing number of \$0\$s at the end of it's base \$10\$ representation. In fact this is true ...
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Sum of two squares
Given a nonnegative integer \$n\$, determine whether \$n\$ can be expressed as the sum of two square numbers, that is \$\exists a,b\in\mathbb Z\$ such that \$n=a^2+b^2\$.
...
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Output a Steiner quadruple system
A Steiner quadruple system \$SQS(n)\$ is a collection of subsets (blocks) of size 4 of a set \$S\$ of size \$n\$ such that every subset of \$S\$ of size 3 is in exactly one block. It is easy to show ...
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Prime a*b+c of N
Given an integer \$N\$, print or return integers \$a\$, \$b\$, and \$c\$ that satisfy all of the following conditions, if such integers exist:
\$a \times b + c = N\$
\$a\$, \$b\$, and \$c\$ are all ...
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Reversed Multiple Pair
Intro
Two numbers are a reversed multiple pair if they satisfy the following property:
$$
a\cdot b = \operatorname{reversed}( (a-1)\cdot b )
$$
Here, \$\operatorname{reversed}()\$ means to reverse the ...
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Infinite-Time Busy Beaver
An infinite time Turing machine is a generalization of a Turing machine to infinite computation lengths. It has three tapes: two of them are blank initially, and the other one contains the input to ...
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Move to Right and left
Task
Your task is to take an array of numbers as input, and produce a new one where each number has been shifted both right and left, leaving 0s if no number fills ...
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Egyptian fractions summing to n
An "Egyptian fraction" is a list of distinct fractions with a numerator of \$1\$. For example:
\$
\frac 1 1+ \frac 1 2 + \frac 1 3 + \frac 1 6
\$
The "size" of an Egyptian ...
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6
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Represent any integer with an expression that uses no digit besides '4' [closed]
Fourward (Introduction)
I have an unhealthy obsession with the number 4. I love it so much, in fact, that seeing any other digit is frustrating to me. I therefour wish to create a 'Fourier ...
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Products all the way down
You are probably familiar with the Cartesian product. It takes two lists and creates a list of all pairs that can be made from an element of the first and an element from the second:
\$
\left[1,2\...
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Egyptian fraction representations of 1
An Egyptian fraction is a representation of a rational number using the sum of distinct unit fractions (a unit fraction is of the form \$ \frac 1 x \$ where \$ x \$ is a positive integer).
For all[1] ...
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Output every sublist ... eventually
You will be given as input an infinite stream of positive integers.
Your task is to write a program which outputs an infinite sequence of lists with two requirements:
All lists in the output are ...
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Generate Fmbalbuena Numbers
My user id is 106959
How to check if the number is Fmbalbuena number?
First Step: Check if the number of digits is a multiple of 3: ...
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Indices of square numbers that are also pentagonal [closed]
First 15 numbers of the A046173:
...
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Iterate your way to a fraction
I recently learned from a comment by MathOverflow user pregunton that it is possible to enumerate all rational numbers using iterated maps of the form \$f(x) = x+1\$ or \$\displaystyle g(x) = -\frac ...
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No parentheses shall be omitted
This expression actually has an omitted pair of parentheses.
1 + 2 * 3
To make things clear, it should be,
1 + (2 * 3)
Even ...
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votes
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Find the absolute minimum difference between 2 divided numbers from n [duplicate]
Input:
An integer n
Output:
A string A * B
Example
12
Possible 2 divisible numbers: ...
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AoCG2021 Day 22: Hyperbolic rescue
Part of Advent of Code Golf 2021 event. See the linked meta post for details.
The story continues from AoC2017 Day 11.
Crossing the bridge, you've barely reached the other side of the stream when you ...
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Find the distance between 2 points in a 3d space (x,y,z) [duplicate]
Your challenge is to create the shortest code that can achieve the above problem given 6 coordinates (x1,y1,z1) (x2,y2,z2)
In python 3, this can be used: (i think im correct hopefully)
...
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AoCG2021 Day 14: Adjusting dancing program's period
Part of Advent of Code Golf 2021 event. See the linked meta post for details.
Related to AoC2017 Day 16. I'm using the wording from my Puzzling SE puzzle based on the same AoC challenge instead of the ...
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Are these the basis vectors?
A basis of a vector space \$V\$ is a set of vectors \$B\$ such that every vector \$\vec v \in V\$ can be uniquely written as a linear combination of the vectors in \$B\$. In other words, let \$B = \{\...
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Total cost of The 12 Days of Christmas
Introduction
I have decided that this Christmas, as a "present" to a friend, I wish to purchase the things described in the classic song "The 12 Days of Christmas". The only ...
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How to solve the LCM in 50 bytes of Python
I've recently stumbled upon a Russian site called acmp.ru, in which one of the tasks, HOK, asks us to find the LCM of two positive integers. The full statement, translated to English is as follows:
...
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Challenge: create a large number using an esoteric programming language [duplicate]
I enjoy large numbers and esoteric programming language, so I decided to combine them into a programming challenge. Your goal is to push the limits of esoteric languages like BF or Pyth and return the ...
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Digit small numbers
A digit small number is a positive integer \$n\$ such for any two numbers that multiply to \$n\$, their total number of digits is more than the digits in \$n\$.
In otherwords: there are no two ...
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Infinite ordinals from a well-ordering
Your task is to write a short program that represents a large (infinite) ordinal, using a well-ordering of the set of positive integers. Your program will take two different positive integers and ...
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When the result will reach the people? [closed]
Assume the result of an exam has been published.
After 5 minutes, First person knows the result.
In next 5 minutes, new 8 persons know the result, and in total 9 know it.
Again after 5 minutes, new 27 ...
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Bijective meets mixed base
Background
A bijective base \$b\$ numeration, where \$b\$ is a positive integer, is a bijective positional notation that makes use of \$b\$ symbols with associated values of \$1,2,\cdots,b\$.
...
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Find the k-th order summary of a number
Background
The summary of a non-negative integer \$n\$ is the concatenation of all digits that appear in \$n\$ in increasing order, with each digit being preceded by the number of times it appears in \...
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How long is the number in this base?
Given a positive integer \$n\$ and another positive integer \$b\$ (\$1 < b < 36\$), return the number of digits/length of \$n\$ in base \$b\$
...
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