\"\"

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Let \"\" be the statement that \"\" for \"\".

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Consider the value of \"\": \"\".

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\"\".

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Thus, \"\" is true.

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Assume \"\" is true, that \"\" for \"\", where \"\" is positive integer.

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Prove that \"\" must be true.

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Use both the parts of inductive hypothesis.

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\"\"

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\"\".

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Add \"\" on each side.

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\"\"

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If \"\" then \"\".

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As \"\" , \"\".

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\"\"

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From (1) and (2):

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\"\" is true for \"\"

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The final statement is exactly \"\", so \"\" is true.

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Because \"\" is true for \"\" and \"\" implies \"\", \"\" is true for \"\" and so on.

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That is, by the principle of mathematical induction, \"\" is true integer values \"\".

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\"\"

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\"\" is true integer values \"\".