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A Theorem on Arithmetic Progression and Divisibility

A Theorem on Arithmetic Progression and Divisibility In this post, we briefly discuss a particular theorem concerning the divisibility of a sequence of terms in arithmetic progression. Before that, let's take a quick review of an arithmetic progression.  Arithmetic Progression: A sequence of numbers that have the same common difference between consecutive terms is said to be an arithmetic progression. For example,  ` 1, 5, 9, 15, 19, ... `  is a sequence of numbers that have a common difference of `4`. Mark that is not the absolute difference but rather algebraic difference. Thus the above is said to be an increasing AP with common difference `4`.  The common difference is taken algebraically as ( any term) - (the previous term). More examples: ` \frac{1}{2} , 1, \frac{3}{2}, 2, \frac{5}{2}, ... ` ` \sqrt{10}, \sqrt{10} - \sqrt{2}, \sqrt{10} - 2\sqrt{2}, ... ` See also that any series of consecutive terms taken from an arithmetic progression also form an arithmetic ...