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 A085243 #5 Apr 16 2024 22:26:29 %S A085243 0,1,1,-1,2,-1,2,1,-2,3,-2,3,1,-3,4,1,-4,5,-4,5,1,-5,6,-5,6,1,-6,7,1, %T A085243 -7,8,-7,8,1,-8,9,-8,9,1,-9,10,-9,10,1,-10,11,1,-11,12,-11,12,1,-12, %U A085243 13,-12,13,1,-13,14,1,-14,15,-14,15,1,-15,16,-15,16,1,-16,17,-16,17 %N A085243 a(n) = A085238(n+1) - A085238(n). %Y A085243 Cf. A085238. %K A085243 sign %O A085243 1,5 %A A085243 _Reinhard Zumkeller_, Jun 22 2003