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%I #16 Sep 08 2022 08:44:57
%S 7,8,10,13,17,23,32,45,64,92,133,193,281,410,599,876,1282,1877,2749,
%T 4027,5900,8645,12668,18564,27205,39869,58429,85630,125495,183920,
%U 269546,395037,578953,848495,1243528,1822477,2670968,3914492,5736965,8407929,12322417
%N Pisot sequence L(7,8).
%H Colin Barker, <a href="/A048588/b048588.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Ph#Pisot">Index entries for Pisot sequences</a>
%F a(n) = 2*a(n-1) - a(n-2) + a(n-3) - a(n-4) (holds at least up to n = 72000 but is not known to hold in general).
%p L := proc(a0,a1,n)
%p option remember;
%p if n = 0 then
%p a0 ;
%p elif n = 1 then
%p a1;
%p else
%p ceil( procname(a0,a1,n-1)^2/procname(a0,a1,n-2)) ;
%p end if;
%p end proc:
%p A048588 := proc(n)
%p L(7,8,n) ;
%p end proc: # _R. J. Mathar_, Feb 12 2016
%t RecurrenceTable[{a[0] == 7, a[1] == 8, a[n] == Ceiling[a[n - 1]^2/a[n - 2]]}, a, {n, 0, 50}] (* _Bruno Berselli_, Feb 05 2016 *)
%o (Magma) Lxy:=[7,8]; [n le 2 select Lxy[n] else Ceiling(Self(n-1)^2/Self(n-2)): n in [1..50]]; // _Bruno Berselli_, Feb 05 2016
%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, 8) \\ _Colin Barker_, Aug 07 2016
%Y See A008776 for definitions of Pisot sequences.
%K nonn
%O 0,1
%A _David W. Wilson_
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