Wikipedia
Alternating series
In mathematics, an alternating series is an infinite series of the form
∑( − 1) a
or ∑( − 1) a
with a > 0 for all n. The signs of the general terms alternate between positive and negative. Like any series, an alternating series converges if and only if the associated sequence of partial sums converges.
Usage examples of "alternating series".
All I need to do is create an alternating series of overlapping fields.