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Sorting integers by their digits (Level 1)
Given a vector, v, of positive integers, return a vector, w, by sorting v in ascending order, such that primary sorting is done ...

2 months ago

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Assignment Problem
Given a matrix where row i corresponds to person i, and column j corresponds to task j and cell (i,j) corresponds to the time ta...

2 months ago

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Find longest run
Write a function longest_run that takes as input an array of 0's and 1's and outputs the length and index of the longest consecu...

2 months ago

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Chek the Delta = p' - p = 6k gap theorem about arithmetic progressions in the prime number set
Context In the prime numbers set there are some arithmetic progressions (sequences of three or more consecutive prime number...

2 months ago

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Linear primes p' = mp + n
Problem statement List the prime numbers of the form p' = mp + n for a given (m,n) couple and such that p' < k, k positive in...

2 months ago

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List the complementary / symetric prime couples
Problem statement For a given positive integer n, provide the prime couples (p,p') such that p + p' = 10^n. NB : a number li...

2 months ago

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Check Legendre's conjecture
Context and problem statement Legendre's conjecture states for a given positive integer n, there always exists at least one pri...

2 months ago

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List the twin prime couples
Problem statement The twin prime couples (p,p') are the ones such that p' = p + 2. For a given integer n > 1, list the twin p...

2 months ago

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Check Bertrand-Chebyshev's theorem about prime numbers
Historical context Bertrand's postulate, also later known as Chebyshev's theorem, is a very important theorem in number theory ...

2 months ago

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Check p = 6n +/- 1, the generic formula for odd prime numbers greater than 3
Problem statement For all odd prime number p greater than 3, there exists a positive integer n, such that p = 6n +/- 1 : ...

2 months ago

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Check p = 4n +/- 1, the generic formula for odd prime numbers
Problem statement For all odd prime number p, there exists a positive integer n, such that p = 4n +/- 1 : Check this f...

2 months ago

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List the near-square primes, p = n² + 1 (Landau's 4th problem)
Historical context At the 1912 International Congress of Mathematicians, Edmund Landau listed four basic problems about prime...

2 months ago

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List primes which are the sum of two consecutive lower primes plus minus one
Problem statement Some prime numbers can be written as the sum of two consecutive lower primes plus / minus one : Like t...

2 months ago

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

3 months ago

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Check p² = 24k + 1, p > 3, the 'golden prime squares' equation
Historical context In december 2023, I / Nicolas Douillet was working on prime squares properties and I found* the formula : ...

3 months ago

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

3 months ago

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

3 months ago

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Build triangulation from -sorted- edge list
Problem statement An edge list is simply a N x 2 matrix of positive integers, in which N is the number of edges and each intege...

3 months ago

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Mesh the convex hull of a random 3D point cloud
Problem statement The convex hull of a 3D point set is actually a first -though rough- triangulation of it. A triangulation,...

3 months ago

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Mesh the icosahedron
Problem statement An icosahedron is a regular polyhedron with 12 vertices and 20 triangular faces. It is also one of the five...

3 months ago

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Mesh the dodecahedron
Problem statement An dodecahedron is a regular polyhedron with 20 vertices and 12 pentagonal faces. It is also one of the fiv...

3 months ago

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Check Euler's characteristic on regular polyhedra
Problem statement Given the number of vertices and the number of faces of a given regular polyhedron, compute the number of its...

3 months ago

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Mesh the square with triangles
Problem statement An square is a regular polygon with 4 vertices and 4 edges. A triangulated mesh T (stands for triangles he...

3 months ago

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Mesh the pentagon (with the minimum number of triangles)
Problem statement An pentagon is a regular polygon with 5 vertices and 5 edges. Here below is an example of the vertex set V,...

3 months ago

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Mesh the tetrahedron
Problem statement An tetrahedron is a regular polyhedron with 4 vertices and 4 triangular faces. It is also one of the five w...

3 months ago

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Mesh the cube
Problem statement : mesh the cube with quadranglar / squared faces An cube / regular hexahedron is a regular polyhedron with ...

3 months ago

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Mesh the octahedron
Problem statement An octahedron is a regular polyhedron with 6 vertices and 8 triangular faces. It is also one of the five we...

3 months ago

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P(girl likes you | she smiled at you)
Compute the probability Given the input probabilities

4 months ago

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

4 months ago

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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