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%I #43 Dec 16 2023 17:12:47
%S 0,1,9,88,855,8311,80784,785233,7632585,74189896,721137159,7009563703,
%T 68134033440,662273246881,6437397456009,62572489832248,
%U 608214190682295,5911935144966391,57464915639473584,558567786770026993,5429364490406558025,52774254921049211176
%N a(0) = 0, a(1) = 1; for n >= 2, a(n) = 9*a(n-1) + 7*a(n-2).
%H Vincenzo Librandi, <a href="/A015583/b015583.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (9,7).
%F G.f.: 1/(1 - 9*x - 7*x^2). - _Zerinvary Lajos_, Dec 20 2008
%p a:=proc(n) option remember: if n=0 then 0 elif n=1 then 1 else 9*procname(n-1)+7*procname(n-2) fi: end; seq(a(n),n=0..22); # _Muniru A Asiru_, Jul 15 2018
%t Join[{a=0,b=1},Table[c=9*b+7*a;a=b;b=c,{n,60}]] (* _Vladimir Joseph Stephan Orlovsky_, Jan 27 2011 *)
%t LinearRecurrence[{9, 7}, {0, 1}, 30] (* _Vincenzo Librandi_, Nov 15 2012 *)
%o (Sage) [lucas_number1(n,9,-7) for n in range(0, 19)] # _Zerinvary Lajos_, Apr 26 2009
%o (Magma) [n le 2 select n-1 else 9*Self(n-1) + 7*Self(n-2): n in [1..30]]; // _Vincenzo Librandi_, Nov 15 2012
%o (PARI) x='x+O('x^30); concat([0], Vec(1/(1-9*x-7*x^2))) \\ _G. C. Greubel_, Jan 06 2018
%o (GAP) a:=[0,1];; for n in [3..22] do a[n]:=9*a[n-1]+7*a[n-2]; od; a; # _Muniru A Asiru_, Jul 15 2018
%Y Cf. A015579, A099371.
%K nonn,easy
%O 0,3
%A _Olivier Gérard_
%E Extended by _T. D. Noe_, May 23 2011
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