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%I #11 Sep 08 2022 08:46:15
%S 1,5,17,25,61,85,109,125,233,305,377,425,497,545,593,625,949,1165,
%T 1381,1525,1741,1885,2029,2125,2341,2485,2629,2725,2869,2965,3061,
%U 3125,4097,4745,5393,5825,6473,6905,7337,7625,8273,8705,9137,9425,9857,10145,10433,10625,11273,11705,12137,12425
%N a(n) = r*a(ceiling(n/2))+s*a(floor(n/2)) with a(1)=1 and (r,s)=(3,2).
%H K.-N. Chang and S.-C. Tsai, <a href="http://dx.doi.org/10.1016/S0020-0190(00)00076-4">Exact solution of a minimal recurrence</a>, Inform. Process. Lett. 75 (2000), 61-64.
%o (PARI) a(n) = if (n==1, 1, 3*a(ceil(n/2))+2*a(floor(n/2))); \\ _Michel Marcus_, Aug 30 2016
%o (Magma) [n le 1 select 1 else 3*Self(Ceiling(n/2))+2*Self(Floor(n/2)): n in [1..60]]; // _Vincenzo Librandi_, Aug 30 2016
%Y Sequences of form a(n) = r*a(ceiling(n/2))+s*a(floor(n/2)) with a(1)=1 and (r,s) = (1,1), (1,2), (2,1), (1,3), (2,2), (3,1), (1,4), (2,3), (3,2), (4,1): A000027, A006046, A064194, A130665, A073121, A268524, A116520, A268525, A268526, A268527.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Feb 16 2016
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