%I
%S 1,2,1,3,4,3,1,2,1,4,3,4,2,1,2,4,3,4,1,2,1,3,4,3,1,2,1,2,1,2,4,3,4,2,
%T 1,2,3,4,3,1,2,1,3,4,3,2,1,2,4,3,4,2,1,2,1,2,1,3,4,3,1,2,1,4,3,4,2,1,
%U 2,4,3,4,1,2,1,3,4,3,1,2,1,3,4,3,1,2,1,3,4,3,2,1,2,4,3,4,2,1,2,3,4,3,1,2,1
%N Fixed point of the morphism 1 > 121, 2 > 343, 3 > 434, 4 > 212, starting from a(0) = 1.
%C Rectangular spacefill from Peano spacefill by row permutation of the digraph matrix: Characteristic polynomial: x^43*x^33*x+9.
%D F. M. Deking, "Recurrent Sets", Advances in Mathematics, vol. 44, no. 1, 1982, page 85, section 4.1
%H <a href="/index/Fi#FIXEDPOINTS">Index entries for sequences that are fixed points of mappings</a>
%F 1>{1, 2, 1}, 2>{3, 4, 3}, 3>{4, 3, 4}, 4>{2, 1, 2}
%t Flatten[ Nest[ Flatten[ # /. {1 > {1, 2, 1}, 2 > {3, 4, 3}, 3 > {4, 3, 4}, 4 > {2, 1, 2}}] &, {1}, 4]] (* _Robert G. Wilson v_ *)
%K nonn
%O 0,2
%A _Roger L. Bagula_, May 03 2005
%E Edited by _Robert G. Wilson v_, Jan 24 2006
