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a(n)=9*a(n-1)+a(n-2), n>2 ; a(0)=1, a(1)=8, a(2)=72 .
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%I #15 Jan 03 2024 08:47:51

%S 1,8,72,656,5976,54440,495936,4517864,41156712,374928272,3415511160,

%T 31114528712,283446269568,2582130954824,23522624862984,

%U 214285754721680,1952094417358104,17783135510944616,162000314015859648

%N a(n)=9*a(n-1)+a(n-2), n>2 ; a(0)=1, a(1)=8, a(2)=72 .

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (9,1).

%F G.f.: (1-x-x^2)/(1-9*x-x^2).

%F a(n) = Sum_{k, 0<=k<=n} A155161(n,k)*8^k. - _Philippe Deléham_, Feb 08 2012

%t LinearRecurrence[{9,1},{1,8,72},20] (* _Harvey P. Dale_, Aug 22 2016 *)

%K nonn,easy

%O 0,2

%A _Philippe Deléham_, Jan 21 2009