Associated Pell numbers which are repdigits or concatenation of two repdigits

In this paper, we show that 1, 3, 7 and 99 are the only associated Pell numbers which are repdigits whereas 17, 41 and 577 are those which are concatenation of two repdigits. As a consequence, we show that 17 and 577 are the only Lucas-balancing numbers which are concatenation of two repdigits.