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 A287474 #17 Feb 16 2025 08:33:46 %S A287474 3,5,31,197,1123,6485,37567,217397,1258051,7280549,42133471,243831461, %T A287474 1411082659,8166108917,47258275711,273489449237,1582717053571, %U A287474 9159378096965,53006446688671,306754821216389,1775227849020643 %N A287474 Number of dominating sets in the n-web graph. %C A287474 Extended to a(0)-a(2) using the recurrence. %H A287474 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/DominatingSet.html">Dominating Set</a> %H A287474 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/WebGraph.html">Web Graph</a> %H A287474 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (5,3,9). %F A287474 G.f.: (-3 + 10*x + 3*x^2)/(-1 + 5*x + 3*x^2 + 9*x^3). %F A287474 a(n) = 5*a(n-1) + 3*a(n-2) + 9*a(n-3). %t A287474 LinearRecurrence[{5, 3, 9}, {5, 31, 197}, {0, 20}] %t A287474 Table[RootSum[-9 - 3 # - 5 #^2 + #^3 &, #^n &], {n, 0, 20}] %t A287474 CoefficientList[Series[(-3 + 10 x + 3 x^2)/(-1 + 5 x + 3 x^2 + 9 x^3), {x, 0, 20}], x] (* _Eric W. Weisstein_, Apr 17 2018 *) %o A287474 (PARI) polsym(-9 - 3*x - 5*x^2 + x^3, 25) \\ _Joerg Arndt_, May 26 2017 %K A287474 nonn,easy %O A287474 0,1 %A A287474 _Eric W. Weisstein_, May 25 2017