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%I #14 Jan 23 2020 17:18:27
%S 1,3,6,10,17,29,48,78,127,207,336,544,881,1427,2310,3738,6049,9789,
%T 15840,25630,41471,67103,108576,175680,284257,459939,744198,1204138,
%U 1948337,3152477,5100816,8253294,13354111,21607407,34961520,56568928
%N a(1)=1, a(n+1)=ceiling(phi*a(n))+1 if a(n) is odd, a(n+1)=ceiling(phi*a(n)) if a(n) is even, where phi=(1+sqrt(5))/2.
%C Closely related to A079472 for terms with an even row. - _Thomas Baruchel_, Jul 28 2005
%F For n>1, a(n) = floor(phi^n*(14+6*sqrt(5))/10) -1
%F (1/10) {4*Lucas(n+3) - 2(-1)^[n/2] - (-1)^[(n-1)/2] - 15 }. - _Ralf Stephan_, Dec 02 2004
%F From _Chai Wah Wu_, Jan 23 2020: (Start)
%F a(n) = 2*a(n-1) - a(n-2) + a(n-3) - a(n-5) for n > 5.
%F G.f.: x*(x^2 + x + 1)/((x - 1)*(x^2 + 1)*(x^2 + x - 1)). (End)
%K nonn
%O 1,2
%A _Benoit Cloitre_, Feb 18 2004
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