A Skolem sequence of order  is a sequence 
 of 
 integers such that 
1. For every ,
 there exist exactly two elements 
 such that 
, and 
2. If 
 with 
,
 then 
.
 
 
	    
	
    
A Skolem sequence of order  is a sequence 
 of 
 integers such that 
1. For every ,
 there exist exactly two elements 
 such that 
, and 
2. If 
 with 
,
 then 
.
 
Weisstein, Eric W. "Skolem Sequence." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/SkolemSequence.html