Bulletin of the Korean Mathematical Society (대한수학회보)

Korean Mathematical Society (대한수학회)
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MULTIPLICATIVE FUNCTIONS WHICH ARE ADDITIVE ON TRIANGULAR NUMBERS

  • Park, Poo-Sung (Department of Mathematics Education Kyungnam University)
  • Received : 2020.05.01
  • Accepted : 2020.12.09
  • Published : 2021.05.31
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Abstract

Fix k ≥ 3. If a multiplicative function f satisfies f(x1 + x2 + ⋯ + xk) = f(x1) + f(x2) + ⋯ + f(xk) for arbitrary positive triangular numbers x1, x2, …, xk, then f is the identity function. This extends Chung and Phong's work for k = 2.

Keywords

Acknowledgement

This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Science and ICT(NRF-2017R1A2B1010761).

References

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