This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A265558 #10 Jun 24 2022 14:07:12
%S A265558 0,1,2,3,4,5,6,7,8,9,11,11,22,33,44,55,66,77,88,99,22,22,22,33,44,55,
%T A265558 66,77,88,99,33,33,33,33,44,55,66,77,88,99,44,44,44,44,44,55,66,77,88,
%U A265558 99,55,55,55,55,55,55,66,77,88,99,66,66,66,66,66,66,66,77,88,99,77,77,77,77,77,77,77,77,88,99,88,88
%N A265558 a(n) = smallest base-10 palindrome m >= n such that every base-10 digit of n is <= the corresponding digit of m.
%H A265558 Rémy Sigrist, <a href="/A265558/b265558.txt">Table of n, a(n) for n = 0..10000</a>
%p A265558 For Maple code see A265543.
%o A265558 (PARI) a(n,base=10) = { my (d=digits(n,base)); for (k=1, #d\2, d[k]=d[#d+1-k]=max(d[k],d[#d+1-k])); fromdigits(d,base) } \\ _Rémy Sigrist_, Jun 24 2022
%Y A265558 Sequences related to palindromic floor and ceiling: A175298, A206913, A206914, A261423, A262038, and the large block of consecutive sequences beginning at A265509.
%Y A265558 Cf. A265525.
%K A265558 nonn,base
%O A265558 0,3
%A A265558 _N. J. A. Sloane_, Dec 10 2015