Lifting-the-exponent lemma
In elementary number theory, the lifting-the-exponent lemma (or LTE lemma) provides several formulas for computing the p-adic valuation ν p {\displaystyle \nu _{p}} of binomial expressions which are differences of powers of integers: that is, how many factors of a prime p {\displaystyle p} are present. The lemma describes the steps necessary to "lift" the exponent of p {\displaystyle p} in such expressions.
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