It's a trivial inequality...but I am curious if there is a popular name for it already. I have not been able to find it through conventional online search.(adsbygoogle = window.adsbygoogle || []).push({});

a_{1}^{2}+ a_{2}^{2}+ ... + a_{n}^{2}> a_{1}*a_{2}+ a_{2}*a_{1}+ a_{2}*a_{3}+ ... + a_{n}*a_{n-1}

Such as:

a^{2}+ b^{2}+ c^{2}> ab + ac + bc + ba + bc + ac = 2(ab + bc + ac)

Which can nicely be envisioned geometrically as sum of squares will always be bigger than corresponding sum of rectangles.

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# A name for this inequality?

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