Dear all,

Let x and y be n-tuples of non-negative integers. Furthermore,

sum x_i = sum y_i

and

sum x_i^2 = sum y_i^2

Is it true that x is necessarily a permutation of y?

Thank you!

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Sorry. I found a way to generate trivial counterexamples.

E.g. x = [16 13 9 4]

y = [17 12 8 5]

etc.