Let
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denote the set of all positive integers. Prove that there exists a unique function
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satisfying
for all
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and
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in
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What is the value of
%V0
Let $\mathbb{N}$ denote the set of all positive integers. Prove that there exists a unique function $f: \mathbb{N} \mapsto \mathbb{N}$ satisfying
$$f(m + f(n)) = n + f(m + 95)$$
for all $m$ and $n$ in $\mathbb{N}.$ What is the value of $\sum^{19}_{k = 1} f(k)?$