Skolem [8] proved that a 1, +1 system exists if and only if n ≡ 0 or 1(mod 4). A 1, +1 system is also known as Skolem sequence, which is defined as follows.
Skolem [8] proved that a 1, +1 system exists if and only if n ≡ 0 or 1(mod4). A 1, +1 system is also known as Skolem sequence, which is defined asfollows.