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%I #19 Jul 02 2023 17:50:14
%S 8,161,2186,26243,295244,3188645,33480782,344373767,3486784400,
%T 34867844009,345191655698,3389154437771,33044255768276,
%U 320275094369453,3088366981419734,29648323021629455,283512088894331672,2701703435345984177
%N a(n) = n*9^n - 1.
%H Vincenzo Librandi, <a href="/A064755/b064755.txt">Table of n, a(n) for n = 1..1000</a>
%H Paul Leyland, <a href="http://www.leyland.vispa.com/numth/factorization/cullen_woodall/cw.htm">Factors of Cullen and Woodall numbers</a>
%H Paul Leyland, <a href="http://www.leyland.vispa.com/numth/factorization/cullen_woodall/gcw.htm">Generalized Cullen and Woodall numbers</a>
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (19, -99, 81).
%F From _Chai Wah Wu_, Feb 01 2018: (Start)
%F a(n) = 19*a(n-1) - 99*a(n-2) + 81*a(n-3) for n > 3.
%F G.f.: x*(81*x^2 - 9*x - 8)/((x - 1)*(9*x - 1)^2). (End)
%t Table[n*9^n-1,{n,20}] (* _Harvey P. Dale_, Feb 28 2017 *)
%o (Magma) [ n*9^n-1: n in [1..20]]; // _Vincenzo Librandi_, Sep 16 2011
%K nonn,easy
%O 1,1
%A _N. J. A. Sloane_, Oct 19 2001
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