%I #21 Sep 08 2022 08:46:04
%S 7,8,5,4,9,8,5,4,9,8,5,4,9,8,5,4,9,8,5,4,9,8,5,4,9,8,5,4,9,8,5,4,9,8,
%T 5,4,9,8,5,4,9,8,5,4,9,8,5,4,9,8,5,4,9,8,5,4,9,8,5,4,9,8,5,4,9,8,5,4,
%U 9,8,5,4,9,8,5,4,9,8,5,4,9,8,5,4,9,8,5,4,9,8,5,4,9
%N Base-n state complexity of partitioned deterministic finite automaton (PDFA) for the periodic sequence (1234)*.
%H Klaus Sutner and Sam Tetruashvili, <a href="http://www.cs.cmu.edu/~sutner/papers/auto-seq.pdf">Inferring automatic sequences</a>.
%F Ultimately periodic with period length 4.
%F G.f.: x^2*(7 + 8*x + 5*x^2 + 4*x^3 + 2*x^4)/(1 - x^4). - _Vincenzo Librandi_, Nov 19 2012
%t Join[{7}, CoefficientList[Series[(8 + 5*x + 4*x^2 + 9x^3)/((1 - x^4)), {x, 0, 30}], x]] (* _Vincenzo Librandi_, Nov 18 2012 *)
%o (Magma) [7] cat &cat[[8, 5, 4, 9]: n in [0..30]]; // _Vincenzo Librandi_, Nov 18 2012
%K nonn
%O 2,1
%A _N. J. A. Sloane_, Oct 07 2012
%E Terms corrected by _Vincenzo Librandi_, Nov 18 2012