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 A110785 #11 Jul 31 2025 10:56:44 %S A110785 1,2,3,4,5,6,7,8,9,11,22,33,44,55,66,77,88,99,101,111,202,212,222,303, %T A110785 313,323,333,404,414,424,434,444,505,515,525,535,545,555,606,616,626, %U A110785 636,646,656,666,707,717,727,737,747,757,767,777,808,818,828,838,848 %N A110785 Palindromes in which the digits are in nonincreasing order halfway through. %H A110785 Paolo Xausa, <a href="/A110785/b110785.txt">Table of n, a(n) for n = 1..10000</a> %e A110785 After 111 the next term is 202 and not 121, 131, up to 191. %t A110785 A110785Q[k_] := PalindromeQ[#] && (Length[#] <= 2 || Min[Differences[#[[;;Ceiling[Length[#]/2]]]]] <= 0) & [IntegerDigits[k]]; %t A110785 Select[Range[2000], A110785Q] (* _Paolo Xausa_, Jul 31 2025 *) %Y A110785 Cf. A002113, A110784. %K A110785 base,easy,nonn %O A110785 1,2 %A A110785 _Amarnath Murthy_, Aug 12 2005