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%I #19 Sep 08 2022 08:45:04
%S 5,71,647,5183,38879,279935,1959551,13436927,90699263,604661759,
%T 3990767615,26121388031,169789022207,1097098297343,7052774768639,
%U 45137758519295,287753210560511,1828079220031487,11577835060199423
%N a(n) = n*6^n - 1.
%H Vincenzo Librandi, <a href="/A064752/b064752.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 (13, -48, 36).
%F a(n) = 13*a(n-1) - 48*a(n-2) + 36*a(n-3); a(1)=5, a(2)=71, a(3)=647. - _Harvey P. Dale_, May 25 2011
%F G.f.: 6*x/(1-6*x)^2+x/(x-1). - _Harvey P. Dale_, May 25 2011
%t Table[n 6^n-1,{n,25}] (* or *) LinearRecurrence[{13,-48,36},{5,71,647}, 25] (* _Harvey P. Dale_, May 25 2011 *)
%o (Magma) [ n*6^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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