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 A261727 #6 Jan 17 2025 14:55:49 %S A261727 1,0,0,2,0,3,0,0,0,25,46,90,172,141,275,601,1102,2199,4150 %N A261727 Length of longest prefix of n-th row in A261712 coinciding with row n+1. %C A261727 A261712(n+1,k) = A261712(n,k) for k = 1 .. a(n). %o A261727 (Haskell) %o A261727 a261727 n = a261727_list !! (n-1) %o A261727 a261727_list = map (length . takeWhile (== 0)) $ %o A261727 zipWith (zipWith (-)) a261712_tabf $ tail a261712_tabf %Y A261727 Cf. A261712, A261646, A261416. %K A261727 nonn,more %O A261727 1,4 %A A261727 _Reinhard Zumkeller_, Aug 31 2015