%I M3088 N1252 #19 Feb 02 2022 00:07:06
%S 1,3,21,6615,64595475
%N Number of stable feedback shift registers with n stages.
%D C. L. Liu, The Stability Problem of Several Classes of Feedback Shift-Registers in Theory of graphs: International Symposium. Held at the International Computation Center in Rome, Jul, 1966. Scientific editor, P. Rosenstiehl; Gordon and Breach, New York; Dunod, Paris 1967, xviii+416 pp. See page 238.
%D N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%K nonn,more
%O 2,2
%A _N. J. A. Sloane_