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 A121477 #7 Aug 27 2024 17:42:33 %S A121477 9,171,252,333,414,11511,12321,13131,21312,22122,31113,1113111, %T A121477 1121211,1211121,2111112,111111111 %N A121477 Zeroless palindromes with digit sum 9. %t A121477 Select[Range[111111111],DigitCount[#,10,0]==0&&Total[IntegerDigits[#]]==9&& PalindromeQ[ #]&] (* _Harvey P. Dale_, Aug 27 2024 *) %Y A121477 Cf. A121476. %K A121477 fini,full,base,nonn %O A121477 1,1 %A A121477 _Lekraj Beedassy_, Aug 01 2006 %E A121477 Corrected by _Harvey P. Dale_, Aug 27 2024