%I #9 Apr 30 2013 22:16:34
%S 16,320,8000,237440,8212736
%N Number of non-degenerate fanout-free Boolean functions of n variables having AND rank 4.
%D J. P. Hayes, Enumeration of fanout-free Boolean functions, J. ACM, 23 (1976), 700-709.
%H <a href="/index/Bo#Boolean">Index entries for sequences related to Boolean functions</a>
%F ~Hayes (1976, Theorem 3) gives a recurrence.
%Y A column of A225171.
%K nonn,more
%O 4,1
%A _N. J. A. Sloane_, Apr 30 2013