  An elliptic divisibility sequence (EDS) is a sequence of integers
W_0,W_1,W_2,... generated by the nonlinear recursion satisfied by the division
polyomials of an elliptic curve. We give a formula for the sign of W_n for
unbounded nonsingular elliptic divisibility sequences. A typical case is
Sign(W_n) = (-1)^[n*b] for an irrational real number b, where [x] denotes the
greatest integer in x. As an application, we show that the associated sequence
of absolute values |W_1|,|W_2|,|W_3|,... cannot be realized as the sequence
counting fixed points of any (abstract) dynamical system.
