Concepts4
∑MathAdvanced
Floor Sum Formula
The floor sum computes S(n,m,a,b) = sum_{i=0}^{n-1} floor((a i + b)/m) efficiently in O(log(min(a,m))) time.
#floor sum#atcoder library#euclidean algorithm+12
∑MathAdvanced
Generating Functions - OGF
An ordinary generating function (OGF) encodes a sequence (a_n) as a formal power series A(x) = \sum_{n \ge 0} a_n x^n.
#ordinary generating function#ogf#coefficient extraction+12
∑MathAdvanced
Berlekamp-Massey Algorithm
Berlekamp–Massey (BM) finds the shortest linear recurrence that exactly fits a given sequence over a field (e.g., modulo a prime).
#berlekamp-massey#linear recurrence#minimal polynomial+11
∑MathAdvanced
Linear Recurrence
A linear recurrence defines each term as a fixed linear combination of a small, fixed number of previous terms.
#linear recurrence#matrix exponentiation#kitamasa+12