Freebase(0.00 / 0 votes)Rate this definition: Grating. A grating is any regularly spaced collection of essentially identical, parallel, elongated elements. Gratings usually consist of a single set of elongated elements, but can consist of two sets, in which case the second set is usually perpendicular to the first.
In mathematics, an arithmetic progression (AP) or arithmetic sequence is a sequence of numbers such that the difference between the consecutive terms is constant.For instance, the sequence 5, 7, 9, 11, 13, 15 â¦ is an arithmetic progression with common difference of 2.If the initial term of an arithmetic progression is and the common difference of successive members is d, then the n th term of the sequence () is given by: and in general.A finite portion of an arithmetic progression is called a finite arithmetic progression and sometimes just called an arithmetic progression.he behavior of the arithmetic progression depends on the common difference d. If the common difference is: 1  Positive, the members (terms) will grow towards positive infinity. 2  Negative, the members (terms) will grow towards negative infinity.
arithmetic (usually uncountable, plural arithmetics) The mathematics of numbers (integers, rational numbers, real numbers, or complex numbers) under the operations of addition, subtraction, multiplication, and division.