Polite Number

In number theory, a polite number is a positive integer that can be written as the sum of two or more consecutive positive integers. Other positive integers are impolite. Polite numbers have also been called staircase numbers because the Young diagrams representing graphically the partitions of a polite number into consecutive integers (in the French style of drawing these diagrams) resemble staircases. If all numbers in the sum are strictly greater than one, the numbers so formed are also called trapezoidal numbers because they represent patterns of points arranged in a trapezoid.

The problem of representing numbers as sums of consecutive integers and of counting the number of representations of this type has been studied by Sylvester, Mason, and Leveque, as well as by many other more recent authors.

Read more about Polite Number:  Examples and Characterization, Politeness, Construction of Polite Representations From Odd Divisors, Trapezoidal Numbers

Famous quotes containing the words polite and/or number:

    “You know, sometimes, when they say you’re ahead of your time, it’s just a polite way of saying you have a real bad sense of timing.”
    —George McGovern (b. 1922)

    “The growing good of the world is partly dependent on unhistoric acts; and that things are not so ill with you and me as they might have been, is half owing to the number who lived faithfully a hidden life, and rest in unvisited tombs.”
    —George Eliot [Mary Ann (or Marian)