# Repdigits as difference of two Pell or Pell-Lucas numbers

## Main Article Content

## Abstract

In this paper, we determine all repdigits, which are difference of two Pell and Pell-Lucas numbers. It is shown that the largest repdigit which is difference of two Pell numbers is $99=169-70=P_{7}-P_{6}$ and the largest repdigit which is difference of two Pell-Lucas numbers is $444=478-34=Q_{7}-Q_{4}.$

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## References

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