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 A064755 #23 May 05 2025 16:21:42
%S A064755 8,161,2186,26243,295244,3188645,33480782,344373767,3486784400,
%T A064755 34867844009,345191655698,3389154437771,33044255768276,
%U A064755 320275094369453,3088366981419734,29648323021629455,283512088894331672,2701703435345984177,25666182635786849690,243153309181138576019
%N A064755 a(n) = n*9^n - 1.
%H A064755 Vincenzo Librandi, <a href="/A064755/b064755.txt">Table of n, a(n) for n = 1..1000</a>
%H A064755 Paul Leyland, <a href="http://www.leyland.vispa.com/numth/factorization/cullen_woodall/cw.htm">Factors of Cullen and Woodall numbers</a>.
%H A064755 Paul Leyland, <a href="http://www.leyland.vispa.com/numth/factorization/cullen_woodall/gcw.htm">Generalized Cullen and Woodall numbers</a>.
%H A064755 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (19,-99,81).
%F A064755 From _Chai Wah Wu_, Feb 01 2018: (Start)
%F A064755 a(n) = 19*a(n-1) - 99*a(n-2) + 81*a(n-3) for n > 3.
%F A064755 G.f.: x*(81*x^2 - 9*x - 8)/((x - 1)*(9*x - 1)^2). (End)
%F A064755 From _Elmo R. Oliveira_, May 05 2025: (Start)
%F A064755 E.g.f.: 1 + exp(x)*(9*x*exp(8*x) - 1).
%F A064755 a(n) = A158749(n) - 1. (End)
%t A064755 Table[n*9^n-1,{n,20}] (* _Harvey P. Dale_, Feb 28 2017 *)
%o A064755 (Magma) [ n*9^n-1: n in [1..20]]; // _Vincenzo Librandi_, Sep 16 2011
%Y A064755 Cf. A003261, A158749.
%K A064755 nonn,easy
%O A064755 1,1
%A A064755 _N. J. A. Sloane_, Oct 19 2001