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 A294140 #50 Feb 16 2025 08:33:51
%S A294140 0,1,16,121,676,3249,14400,61009,252004,1026169,4145296,16670889,
%T A294140 66879684,267944161,1072693504,4292739361,17175150916,68709515625,
%U A294140 274856935824,1099467588025,4397954236900,17591993106961,70368341525056,281474137850481,1125898162012836
%N A294140 Number of total dominating sets in the n-crown graph.
%C A294140 In a total dominating set each side of the crown graph requires any two vertices on the other side to dominate it. - _Andrew Howroyd_, Apr 16 2018
%H A294140 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/CrownGraph.html">Crown Graph</a>
%H A294140 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/TotalDominatingSet.html">Total Dominating Set</a>
%H A294140 <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (11,-47,101,-116,68,-16).
%F A294140 a(n) = (2^n - 1 - n)^2. - _Andrew Howroyd_, Apr 16 2018
%F A294140 a(n) = 11*a(n-1) - 47*a(n-2) + 101*a(n-3) - 116*a(n-4) + 68*a(n-5) -16*a(n-6).
%F A294140 G.f.: x^2*(1 + 5*x - 8*x^2 - 4*x^3)/((-1 + x)^3*(-1 + 2*x)^2*(-1 + 4*x)).
%t A294140 Table[(1 - 2^n + n)^2, {n, 20}]
%t A294140 LinearRecurrence[{11, -47, 101, -116, 68, -16}, {0, 1, 16, 121, 676, 3249}, 20]
%t A294140 CoefficientList[Series[x (1 + 5 x - 8 x^2 - 4 x^3)/((-1 + x)^3 (-1 + 2 x)^2 (-1 + 4 x)), {x, 0, 20}], x]
%o A294140 (PARI) a(n)=(2^n-1-n)^2; \\ _Andrew Howroyd_, Apr 16 2018
%Y A294140 Cf. A287063, A287471.
%K A294140 nonn,easy
%O A294140 1,3
%A A294140 _Eric W. Weisstein_, Apr 16 2018
%E A294140 a(1)-a(2) and a(11)-a(25) from _Andrew Howroyd_, Apr 16 2018