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%I #13 Jan 12 2025 14:55:57
%S 0,2,3,6,12,25,52,109,228,477,999,2093,4385,9188,19251,40336,84516,
%T 177085,371045,777448,1628982,3413196,7151649,14984807,31397576,
%U 65787152,137843423,288822495,605168036
%N a(n) = floor(tau*a(n-1)) + a(n-2) with a(0)=0 and a(1)=2.
%t nxt[{a_,b_}]:={b,Floor[b*GoldenRatio]+a}; NestList[nxt,{0,2},30][[All,1]] (* _Harvey P. Dale_, Apr 11 2018 *)
%K nonn
%O 0,2
%A _N. J. A. Sloane_