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%I #16 Dec 26 2016 11:13:13
%S 4,10,25,62,153,377,928,2284,5621,13833,34042,83774,206159,507335,
%T 1248496,3072412,7560869,18606469,45788478,112680418,277294139,
%U 682390435,1679287948,4132543288,10169735361,25026602289,61587720810,151560619806,372974046999
%N Pisot sequence T(4,10), a(n) = floor(a(n-1)^2/a(n-2)).
%H Colin Barker, <a href="/A020748/b020748.txt">Table of n, a(n) for n = 0..1000</a>
%F G.f.: (-3x^5+2x^4+x^3-x^2-2x+4)/[(1-x)(1-2x-x^2-2x^5)] (conjectured). - _Ralf Stephan_, May 12 2004
%F Note the warning in A010925 from Pab Ter (pabrlos(AT)yahoo.com), May 23 2004: [A010925] and other examples show that it is essential to reject conjectured generating functions for Pisot sequences until a proof or reference is provided. - _N. J. A. Sloane_, Jul 26 2016
%t RecurrenceTable[{a[0]==4,a[1]==10,a[n]==Floor[a[n-1]^2/a[n-2]]},a,{n,30}] (* _Harvey P. Dale_, Dec 26 2016 *)
%o (PARI) pisotT(nmax, a1, a2) = {
%o a=vector(nmax); a[1]=a1; a[2]=a2;
%o for(n=3, nmax, a[n] = floor(a[n-1]^2/a[n-2]));
%o a
%o }
%o pisotT(50, 4, 10) \\ _Colin Barker_, Jul 29 2016
%Y See A008776 for definitions of Pisot sequences.
%K nonn
%O 0,1
%A _David W. Wilson_
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