enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Floor and ceiling functions - Wikipedia

    en.wikipedia.org/wiki/Floor_and_ceiling_functions

    In mathematics, the floor function (or greatest integer function) is the function that takes as input a real number x, and gives as output the greatest integer less than or equal to x, denoted ⌊x⌋ or floor (x). Similarly, the ceiling function maps x to the smallest integer greater than or equal to x, denoted ⌈x⌉ or ceil (x).

  3. Identity function - Wikipedia

    en.wikipedia.org/wiki/Identity_function

    Identity function. In mathematics, an identity function, also called an identity relation, identity map or identity transformation, is a function that always returns the value that was used as its argument, unchanged. That is, when f is the identity function, the equality f(x) = x is true for all values of x to which f can be applied.

  4. Euler's totient function - Wikipedia

    en.wikipedia.org/wiki/Euler's_totient_function

    In number theory, Euler's totient function counts the positive integers up to a given integer n that are relatively prime to n. It is written using the Greek letter phi as or , and may also be called Euler's phi function. In other words, it is the number of integers k in the range 1 ≤ k ≤ n for which the greatest common divisor gcd (n, k ...

  5. Laplace transform - Wikipedia

    en.wikipedia.org/wiki/Laplace_transform

    Laplace transform. In mathematics, the Laplace transform, named after Pierre-Simon Laplace ( / ləˈplɑːs / ), is an integral transform that converts a function of a real variable (usually , in the time domain) to a function of a complex variable (in the complex-valued frequency domain, also known as s-domain, or s-plane ).

  6. Partition function (number theory) - Wikipedia

    en.wikipedia.org/wiki/Partition_function_(number...

    In number theory, the partition function p(n) represents the number of possible partitions of a non-negative integer n. For instance, p(4) = 5 because the integer 4 has the five partitions 1 + 1 + 1 + 1, 1 + 1 + 2, 1 + 3, 2 + 2, and 4 . No closed-form expression for the partition function is known, but it has both asymptotic expansions that ...

  7. Formulas for generating Pythagorean triples - Wikipedia

    en.wikipedia.org/wiki/Formulas_for_generating...

    Using tangent half-angle formulas, it follows immediately that α = sin A = 2r / (1 + r2) and β = cos A = (1 − r2) / (1 + r2) are both rational and that α2 + β2 = 1. Multiplying up by the smallest integer that clears the denominators of α and β recovers the original primitive Pythagorean triple.

  8. Arithmetic function - Wikipedia

    en.wikipedia.org/wiki/Arithmetic_function

    In number theory, an arithmetic, arithmetical, or number-theoretic function [1] [2] is generally any function f ( n) whose domain is the positive integers and whose range is a subset of the complex numbers. [3] [4] [5] Hardy & Wright include in their definition the requirement that an arithmetical function "expresses some arithmetical property ...

  9. Möbius transformation - Wikipedia

    en.wikipedia.org/wiki/Möbius_transformation

    The existence of the inverse Möbius transformation and its explicit formula are easily derived by the composition of the inverse functions of the simpler transformations. That is, define functions g 1, g 2, g 3, g 4 such that each g i is the inverse of f i.