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 A243251 #12 Feb 16 2025 08:33:22 %S A243251 0,0,0,0,1,3,33,496,16464,969293 %N A243251 Number of simple connected graphs with n nodes whose fractional chromatic number is not equal to its (integer) chromatic number. %C A243251 This implies that there is a gap between the corresponding integer and linear programs defining fractional colorings. Every simple graph has a fractional chromatic number which is a rational number or integer. %H A243251 Travis Hoppe and Anna Petrone, <a href="https://github.com/thoppe/Encyclopedia-of-Finite-Graphs">Encyclopedia of Finite Graphs</a> %H A243251 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/FractionalChromaticNumber.html">Fractional Chromatic Number</a> %F A243251 a(n) = A001349(n) - A243252(n). - _Andrew Howroyd_, Nov 03 2017 %Y A243251 Cf. A243252 (fractional chromatic number is equal to chromatic number) %K A243251 nonn,more %O A243251 1,6 %A A243251 _Travis Hoppe_ and _Anna Petrone_, Jun 20 2014 %E A243251 Name edited by _Michel Marcus_, Jan 12 2025