arXiv · 2609.23901
For any positive integer $k$, let $J_{k}$ be Jordan's totient function. We show that $J_{k}$ is not injective when $k=3,4,6$.
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Hang Fu. 2026-09-20. On the noninjectivity of Jordan's totient functions. https://arxiv.org/abs/2609.23901
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