Repdigits base b as products of two Pell numbers or Pell–Lucas numbers

In this paper, we determine all repdigits in base b for 2 ≤ b ≤ 10 , which are products of two Pell numbers or Pell–Lucas numbers. It is shown that the largest Pell number which is a base b -repdigit is P 6 = 70 = ( 77 ) 9 = 7 + 7 · 9 . Also, we give the result that the equations P m P n + 1 = b k and Q m Q n + 1 = b k have no solutions for n ≥ 5 and n ≥ 1 , respectively, where 1 ≤ m ≤ n .