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 A251551 #10 Dec 19 2014 14:16:46 %S A251551 -1,1,-1,1,1,1,1,1,-1,3,3,3,3,3,-1,7,7,7,7,7,7,5,1,1,1,1,1,1,1,-1,5,5, %T A251551 11,11,11,11,11,11,19,19,21,21,17,17,17,17,17,23,23,23,17,17,17,17,17, %U A251551 25,25,25,25,25,23,17 %N A251551 a(n) = A251546(n) - A251549(n). %H A251551 Chai Wah Wu, <a href="/A251551/b251551.txt">Table of n, a(n) for n = 1..10000</a> %o A251551 (Haskell) %o A251551 a251551 n = a251546 n - a251549 n -- _Reinhard Zumkeller_, Dec 19 2014 %Y A251551 Cf. A098550, A247253, A251416, A251417, A251546-A251552. %K A251551 sign %O A251551 1,10 %A A251551 _N. J. A. Sloane_, Dec 18 2014