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 A045627 #6 Mar 30 2012 18:35:35 %S A045627 1,1,3,9,34,125,459,1715,6432,24300,92375,352715,1352034,5200299, %T A045627 20058297,77558625,300540160,1166803109,4537567188,17672631899, %U A045627 68923264250,269128935495,1052049481857,4116715363799,16123801834656 %N A045627 Number of 2n-bead black-white reversible strings with n black beads and fundamental period 2n. %F A045627 Moebius transform of A032123(n+1) (Christian Bower). %K A045627 nonn %O A045627 0,3 %A A045627 _David W. Wilson_