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Number of ascending runs in {1,...,8}^n.
2

%I #11 Jul 01 2023 16:00:37

%S 0,8,100,1088,11008,106496,999424,9175040,82837504,738197504,

%T 6509559808,56908316672,493921239040,4260607557632,36558761623552,

%U 312261302288384,2656420092706816,22517998136852480,190277084256403456,1603281467343896576,13474770085092524032

%N Number of ascending runs in {1,...,8}^n.

%H Alois P. Heinz, <a href="/A229282/b229282.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 (16,-64).

%F G.f.: -4*(7*x-2)*x/(8*x-1)^2.

%F a(n) = 2^(3*n-4)*(9*n+7) for n>0, a(0) = 0.

%p a:= n-> `if`(n=0, 0, 2^(3*n-4)*(9*n+7)):

%p seq(a(n), n=0..30);

%Y Column k=8 of A229079.

%K nonn,easy

%O 0,2

%A _Alois P. Heinz_, Sep 18 2013