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 A382164 #9 Mar 26 2025 08:28:40 %S A382164 909090909,9090909090909090909090909090909, %T A382164 81188118811881188118811881188118,545545545545545545545545545545545, %U A382164 277227722772277227722772277227722772,505050505050505050505050505050505050505,4040404040404040404040404040404040404040404040404 %N A382164 Palindromic Kaprekar numbers that are not repdigit Kaprekar numbers. %C A382164 [The data is copied from Gupta (2025); it would be nice to have it confirmed.] %H A382164 Shyam Sunder Gupta, <a href="https://doi.org/10.1007/978-981-97-2465-9_9">On Some Marvellous Numbers of Kaprekar</a>, Exploring the Beauty of Fascinating Numbers, Springer (2025) Ch. 9, 275-315. See Section 9.2.4. %Y A382164 Cf. A006886. %Y A382164 A382163 is the union of this sequence and A145875. %K A382164 nonn,base %O A382164 1,1 %A A382164 _N. J. A. Sloane_, Mar 26 2025