Back to Minimum overlap problem

n = 6
for 0x < 1/3
for 1/3x < 2/3
for 2/3x ≤ 1
f(x) = f(2-x)for 1< x ≤ 2
Illustration
α(f) = 7/18 < 0.38888889
 maximal for |k| ≤ 2/3