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 A080915 #2 Mar 30 2012 18:41:15 %S A080915 1,2,1,2,3,4,5,6,7,8,1,2,3,4,5,6,7,8,1,2,2,2,2,1,2,2,2,2,1,2,3,4,5,6, %T A080915 7,8,1,2,2,2,1,1,2,1,1,10,1,2,3,4,5,6,7,8,1,2,2,2,2,2,2,2,2,2,2,2,2,2, %U A080915 2,2,2,2,2,2,2,2,2,1,1,2,3,4,5,6,7,8,1,2,2,2,2,2,2,2,2,2,2,2 %N A080915 Number of electrons in outermost electron shell (valence electrons) in chemical element number n. %H A080915 C. Heilman, <a href="http://chemlab.pc.maricopa.edu/periodic/periodic.html">The Pictorial Periodic Table</a> %e A080915 Example: element 46Pd has ten electrons in its N-shell, none in its O-shell. %Y A080915 Cf. A080916. %K A080915 nonn %O A080915 0,2 %A A080915 _Ralf Stephan_, Feb 23 2003