Inverse of the transformation $X \mapsto Y = X\cdot X^t$

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I have a Matrix Y of Kind : $n\cdot I$ where $I$ is the identity Matrix of size $n\times n$ , I need to find Matrix $X$ if it exists such that all elements are either 1 or -1 and satisfies $XX^t$ = $Y$. Please Help

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To get $XX^T=nI$, you need

(1) The columns vectors to be orthgonal,

(2) with length $\sqrt{n}$

If each entry is -1 or 1, (2) will always be satisfied. Also, the inner product between column vectors will be odd or even, based on whether n is odd or even. An odd n therefore will never work. N has to be even. you just have to set them up as mutually orthogonal.