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 A058318 #47 Apr 25 2024 11:35:49 %S A058318 1,1,2,2,2,2,2,2,2,2,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4, %T A058318 4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,6,6,6,6,6,6,6,6,6,6,6,6,6,6, %U A058318 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7 %N A058318 Number of energy levels in atoms of the n-th element of the periodic table. %C A058318 Run lengths, i.e., how many elements have 1,2,3,4,5,6,7 energy levels, are 2,8,8,18,18,32,26 (see A137583). %H A058318 Y. Bentor, <a href="http://www.chemicalelements.com/">Chemical Elements.Com</a> %H A058318 M. Winter, <a href="http://www.webelements.com/webelements/scholar/index.html">WebElements Periodic Table</a>. %F A058318 a(n) = m for s(m-1) < n <= s(m) for m=1..7, where s(m) = A173592(m) and s(0) = 0. - _Michel Lagneau_, Apr 03 2024 %e A058318 For n=79, element 79 (Gold) has a(79)=6 energy levels (which may have 2,8,18,32,18,1 electrons). %p A058318 seq(i$[2, 8, 8, 18, 18, 32, 32][i], i=1..7); # _Michel Lagneau_, Apr 03 2024 %Y A058318 Cf. A007656, A018227, A058317, A137583, A173592. %K A058318 nonn,fini,full %O A058318 1,3 %A A058318 _Labos Elemer_, Dec 12 2000 %E A058318 a(106)-a(118) from _Michel Lagneau_, Apr 03 2024