The bias of a series is defined as
![Q[a_i,a_(i+1),a_(i+2)]=(a_ia_(i+2)-a_(i+1)^2)/(a_ia_(i+1)a_(i+2)).](/images/equations/SeriesBias/NumberedEquation1.svg) |
A series is geometric iff 
.
A series is artistic iff the bias is constant.
Series Bias
See also
Artistic Sequence, Geometric SequenceExplore with Wolfram|Alpha
References
Duffin, R. J. "On Seeing Progressions of Constant Cross Ratio." Amer. Math. Monthly 100, 38-47, 1993.Referenced on Wolfram|Alpha
Series BiasCite this as:
Weisstein, Eric W. "Series Bias." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/SeriesBias.html