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 A087756 #18 Jul 10 2017 02:53:09 %S A087756 1,3,3,5,5,15,15,17,17,51,51,85,85,255,255,257,257,771,771,1285,1285, %T A087756 3855,3855,4369,4369,13107,13107,21845,21845,65535,65535,65537,65537, %U A087756 196611,196611,327685,327685,983055,983055,1114129,1114129 %N A087756 a(n) = A087745(n+1). %C A087756 Essentially a duplicate of A087745. %C A087756 Mitrinovic's triangles A049458, A049460, A051339, A051380 and triangle of Stirling numbers of first kind (A008275) mod 2 converted to decimal. %C A087756 See also A001317 = [1, 3, 5, 15, 17, ...]. %Y A087756 Cf. A001317, A008275, A049458, A049460, A051339, A051380. %K A087756 base,easy,nonn,less %O A087756 0,2 %A A087756 _Philippe Deléham_, Oct 02 2003 %E A087756 Edited by _Omar E. Pol_ and _N. J. A. Sloane_, Dec 26 2008