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 A251552 #10 Dec 19 2014 14:16:33 %S A251552 -1,0,-1,0,0,0,0,0,-1,1,1,1,1,1,-1,3,3,3,3,3,3,2,0,0,0,0,0,0,0,-1,2,2, %T A251552 5,5,5,5,5,5,9,9,10,10,8,8,8,8,8,11,11,11,8,8,8,8,8,12,12,12,12,12,11, %U A251552 8,8,8,8,8,8,8 %N A251552 a(n) = (A251551(n)-1)/2. %H A251552 Chai Wah Wu, <a href="/A251552/b251552.txt">Table of n, a(n) for n = 1..10000</a> %o A251552 (Haskell) %o A251552 a251552 = flip div 2 . subtract 1 . a251551 %o A251552 -- _Reinhard Zumkeller_, Dec 19 2014 %Y A251552 Cf. A098550, A247253, A251416, A251417, A251546-A251551. %K A251552 sign %O A251552 1,16 %A A251552 _N. J. A. Sloane_, Dec 18 2014