  It is speculated that there is a relationship between 1/f noise and
computational universality in cellular automata. We use genetic algorithms to
search for one-dimensional and two-state, five-neighbor cellular automata which
have 1/f-type spectrum. A power spectrum is calculated from the evolution
starting from a random initial configuration. The fitness is estimated from the
power spectrum in consideration of the similarity to 1/f-type spectrum. The
result shows that the rule with the highest average fitness has a propagating
structure like other computationally universal cellular automata, although
computational universality of the rule has not been proved yet.
