# On the last digits of tetrations of base $2^{k}$ and $5^{k}$

@inproceedings{Onnis2021OnTL, title={On the last digits of tetrations of base \$2^\{k\}\$ and \$5^\{k\}\$}, author={Luca Onnis}, year={2021} }

In this paper will be proved the existence of a formula to reduce a tetration [4] of base 2 and 5 mod 10. Indeed, last digits of a tetration are the same starting from a certain hyper-exponent; In order to compute the last digits of those expressions we reduce them mod 10. Lots of different formulas will be derived, for different cases of k (where k is the exponent of the base of the tetration). This kind of operation is fascinating, because the tetration grows very fast. But using these… Expand

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Observations regarding the repetition of the last digits of a tetration of generic base

- Mathematics
- 2021

This paper investigates the behavior of the last digits of a tetration [3]of generic base. In fact, last digits of a tetration are the same starting from a certain hyper-exponent and in order to… Expand

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