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Pisot sequence L(7,10).
3

%I #17 Jun 10 2022 09:26:51

%S 7,10,15,23,36,57,91,146,235,379,612,989,1599,2586,4183,6767,10948,

%T 17713,28659,46370,75027,121395,196420,317813,514231,832042,1346271,

%U 2178311,3524580,5702889,9227467,14930354,24157819,39088171,63245988,102334157,165580143

%N Pisot sequence L(7,10).

%H Colin Barker, <a href="/A020743/b020743.txt">Table of n, a(n) for n = 0..1000</a>

%H <a href="/index/Ph#Pisot">Index entries for Pisot sequences</a>

%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (2,0,-1).

%F a(n) = Fib(n+5)+2 = A157725(n+5). a(n) = 2a(n-1) - a(n-3).

%t LinearRecurrence[{2,0,-1},{7,10,15},40] (* _Harvey P. Dale_, Jun 10 2022 *)

%o (PARI) pisotL(nmax, a1, a2) = {

%o a=vector(nmax); a[1]=a1; a[2]=a2;

%o for(n=3, nmax, a[n] = ceil(a[n-1]^2/a[n-2]));

%o a

%o }

%o pisotL(50, 7, 10) \\ _Colin Barker_, Aug 07 2016

%Y Subsequence of A018910. See A008776 for definitions of Pisot sequences.

%Y Cf. A020717.

%K nonn,easy

%O 0,1

%A _David W. Wilson_