Solved

My wife's logic
Its is always the opposite of the causality law, that is to say the implication relationship in math/logic terms : Figure...

4 months ago

Problem

List even numbers whose Goldbach partition does not use the largest prime
The strong Goldbach conjecture says that every even number greater than 2 can be expressed as a sum of two prime numbers—that is...

4 months ago | 1 | 6 solvers

Solved

Extra colors
Context In the RGB color system used by Matlab, the color is a 1 x 3 / row vector [R G B] with each value/component R, G, B in ...

4 months ago

Problem

Find the longest runs of primes generated by polynomials
Cody Problems 60942, 60943, and 60944 involve polynomials that generate primes. No polynomial can generate only prime numbers, b...

4 months ago | 2 | 6 solvers

Solved

Check the integers decomposition conjecture
Problem statement A conjecture (I rediscovered ?) related to Goldbach's one states that every integer above 2 can be written ...

4 months ago

Solved

Check the 'golden prime squares' equation
Historical context In december 2023, I / Nicolas Douillet was working on prime squares properties and I found* the formula : ...

4 months ago

Solved

Euclid primes
Historical context Euclid, the greek mathematician proved at his time that the prime numbers set is an infinite. By the way he ...

4 months ago

Solved

Fermat primes
Historical context The french mathematician Pierre de Fermat found the formula to find some prime numbers. He thought / co...

4 months ago

Problem

Compile evidence for the Carmichael totient conjecture
The totient function counts the positive integers up to that are relatively prime to . The Carmichael totient conjecture state...

4 months ago | 2 | 4 solvers

Solved

Ulam primes first formula
Historical context The polish-american mathematician Stanislaw Ulam found the formula to give the first 760 prime numbers ...

4 months ago

Solved

Ulam primes second formula
Historical context The polish-american mathematician Stanislaw Ulam found the formula to give some prime numbers not given...

4 months ago

Solved

Euler primes
Historical context The great swiss mathematician Leonhard Euler found the formula to give some prime numbers. Problem...

4 months ago

Solved

Primes numbers which are the difference of two consecutive cubes
Problem statement Given a positive integer n greater than 2, find the prime numbers less or equal to n and which are the diff...

4 months ago

Solved

Find the first occurence of a given gap between two consecutive prime numbers
Given a gap = p' - p between the two consecutive prime numbers p and p', find its first occurence, f. For examples : If , f=...

4 months ago

Solved

Frequencies of prime gaps
Given two positive integers n and , write a function which computes the frequency of the gap between two consecutive of the pr...

4 months ago

Solved

Breaking up a chocolate bar
You've got a chocolate bar of size , and you want to break it up into bite-sized () pieces. How many steps are required to do th...

4 months ago

Solved

The cake is a lie...
You're hosting a birthday party with a large number of screaming children. Fortunately, you have a gigantic sheet cake in front...

4 months ago

Solved

Dominant Matrix - 02
It is a follow-up of the problem 55995. There, you found out whether a matrix is diagonally dominant or not. In this problem, y...

4 months ago

Problem

Classify triangles as acute, obtuse, or right
In an acute triangle, the three interior angles are acute, or smaller than 90 degrees. In an obtuse triangle, one angle is obtus...

4 months ago | 0 | 9 solvers

Problem

Compute the antisigma function
The sum of divisors function, or , is the sum of the numbers that divide . The antisigma function is the sum of numbers less tha...

5 months ago | 0 | 8 solvers

Solved

Symmetric Pair
Given an (n, 2) matrix, remove any symmetric pairs from the matrix. Keep the first occurrence. (2, 3) and (3, 2) are considere...

5 months ago

Solved

Pairs with Given Sum
Given an array of integers and a target sum, return all unique pairs whose sum is equal to the target. The output should be a ma...

5 months ago

Solved

Last Duplicate
Given an array of integers, find the last duplicate element — that is, the element whose second occurrence appears latest in the...

5 months ago

Solved

First Duplicate
Given an array of integers, return the first duplicate — i.e., the element that appears more than once and whose second appearan...

5 months ago

Solved

Most Frequent Characters
Given a document file or a character array, identify the 'n' most frequently occurring characters and the number of times each a...

5 months ago

Solved

Juros Simples
Faça uma função que calcule o montagem de um investimento com juros simples que receba como argumentos o capital inicial C, a ta...

5 months ago

Solved

Greater than before
Given an array of integers, write a function that returns elements that are greater than the one before them. For instance, ...

5 months ago

Solved

Unique rows
A matrix is given as the input. Remove any duplicate rows from the matrix. keep the first occurrence.

5 months ago

Solved

'X'avier
Given a square matrix A of size n, write a function to create a new matrix B where only the elements on the main diagonal and th...

5 months ago

Problem

Intersect three sequences
Most numbers have interesting properties, if you look hard enough and interpret “interesting” liberally. Let’s choose a number a...

5 months ago | 0 | 2 solvers