If ${ A }_{ 1 },{ A }_{ 2 },...,{ A }_{ n }$ be the vertices of a $n$- sided regular polygon such that:$\frac { 1 }{ { A }_{ 1 }{ A }_{ 2 } } =\frac { 1 }{ { A }_{ 1 }{ A }_{ 3 } } +\frac { 1 }{ { A }_{ 1 }{ A }_{ 4 } }$Then find the value of $n$

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