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%I #6 Sep 08 2017 09:37:20
%S 0,1,15,90,435,1926,8175,33930,139035,565326,2287335,9224370,37116435,
%T 149110326,598350495,2399080410,9613258635,38503648926,154166045655,
%U 617117746050,2469830101635,9883394613126,39545794780815,158219815525290,632989146141435
%N Wiener index of the n-Mycielski graph.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/MycielskiGraph.html">Mycielski Graph</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/WienerIndex.html">Wiener Index</a>
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (10,-35,50,-24).
%F a(n) = (216 - 27*2^(n + 3) - 56*3^n + 81*4^n)/144 for n > 1.
%F a(n) = 10*a(n-1) - 35*a(n-2) + 50*a(n-3) - 24*a(n-4).
%F G.f.: x^2*(1 + 5*x - 25*x^2 + 10*x^3)/(1 - 10*x + 35*x^2 - 50*x^3 + 24*x^4).
%t Table[If[n == 1, 0, (216 - 27 2^(n + 3) - 56 3^n + 81 4^n)/144], {n,
%t 30}]
%t Join[{0}, LinearRecurrence[{10, -35, 50, -24}, {1, 15, 90, 435}, 20]]
%t CoefficientList[Series[x (1 + 5 x - 25 x^2 + 10 x^3)/(1 - 10 x + 35 x^2 - 50 x^3 + 24 x^4), {x, 0, 20}], x]
%K nonn,easy
%O 1,3
%A _Eric W. Weisstein_, Sep 08 2017
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