Un cuadrado mágico es una tabla de grado primario donde se dispone de una serie de números enteros en un cuadrado o matriz de forma tal que la suma de los números por columnas, filas y diagonales principales sea la misma.Usualmente los números empleados para rellenar las casillas son consecutivos, de 1 a n², siendo n el número de columnas y filas del cuadrado mágico. Los cuadrados mágicos actualmente no tienen ninguna aplicación técnica conocida que se beneficien de estas características, por lo que sigue recluido al divertimento, curiosidad y al pensamiento matemático. Aparte de esto, en las llamadas ciencias ocultas y más concretamente en la magia tienen un lugar destacado.

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In recreational mathematics, a magic square is an arrangement of distinct numbers (i.e., each number is used once), usually integers, in a square grid, where the numbers in each row, and in each column, and the numbers in the main and secondary diagonals, all add up to the same number, called the "magic constant." A magic square has the same number of rows as it has columns, and in conventional math notation, "n" stands for the number of rows (and columns) it has. Thus, a magic square always contains n2 numbers, and its size (the number of rows [and columns] it has) is described as being "of order n." A magic square that contains the integers from 1 to n2 is called a normal magic square. (The term "magic square" is also sometimes used to refer to any of various types of word squares.) Normal magic squares of all sizes except 2×2 (that is, where n = 2) can be constructed. The 1×1 magic square, with only one cell containing the number 1, is trivial. The smallest (and unique up to rotation and reflection) non-trivial case, 3×3, is shown below. File:Magicsquareexample.svg Any magic square can be rotated and reflected to produce 8 trivially distinct squares. In magic square theory, all of these are generally deemed equivalent and the eight such squares are said to make up a single equivalence class. The constant that is the sum of every row, column and diagonal is called the magic constant or magic sum, M. Every normal magic square has a constant dependent on n, calculated by the formula M = [n(n2 + 1)] / 2. For normal magic squares of order n = 3, 4, 5, 6, 7, and 8, the magic constants are, respectively: 15, 34, 65, 111, 175, and 260 (sequence A006003 in the OEIS). Magic squares have a long history, dating back to 650 BC in China. At various times they have acquired magical or mythical significance, and have appeared as symbols in works of art. In modern times they have been generalized a number of ways, including using extra or different constraints, multiplying instead of adding cells, using alternate shapes or more than two dimensions, and replacing numbers with shapes and addition with geometric operations.

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