A sequence 
is said to be periodic with period 
with if it satisfies 
for 
, 2, .... For example, 
is a periodic sequence with
least period 2.
Periodic Sequence
See also
Eventually Periodic, Periodic Function, Periodic PointExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Periodic Sequence." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/PeriodicSequence.html