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%I #28 May 06 2015 07:02:19
%S 9,71,4969,24685991,609398126966089,371366077149776919833628989831,
%T 137912763257614063309949706968500684963726537144819872418729
%N Recurrence sequence a(n)=a(n-1)^2-a(n-1)-1, a(0)=9.
%C The original version of this sequence had a(0)=5=A144743(1) and therefore was essentially the same as that sequence A144743.
%C The next term a(8) has 119 digits.
%F a(n) = a(n-1)^2-a(n-1)-1 and a(0)=9.
%F a(n) ~ c^(2^n), where c = 8.395688554881795978328174160925857176207363473280394010762212170489... . - _Vaclav Kotesovec_, May 06 2015
%t k = 9; a = {k}; Do[k = k^2 - k - 1; AppendTo[a, k], {n, 1, 10}]; a
%t NestList[#^2 - # - 1 &, 9, 7] (* _Harvey P. Dale_, Feb 04 2011 *)
%o (PARI) a(n,s=9)=for(i=1,n,s=s^2-s-1);s \\ _M. F. Hasler_, Oct 06 2014
%Y Cf. A000058, A082732, A144743, A144744, A144746, A144747, A144748.
%K nonn
%O 0,1
%A _Artur Jasinski_, Sep 20 2008
%E New initial value a(0)=9 from _M. F. Hasler_, Oct 20 2014