let n1, n2, n3 be Element of NAT ; for S being Gene-Set
for p1, p2 being Individual of S holds crossover (p1,p2,n1,n2,n3) = crossover (p1,p2,n3,n1,n2)
let S be Gene-Set; for p1, p2 being Individual of S holds crossover (p1,p2,n1,n2,n3) = crossover (p1,p2,n3,n1,n2)
let p1, p2 be Individual of S; crossover (p1,p2,n1,n2,n3) = crossover (p1,p2,n3,n1,n2)
crossover (p1,p2,n1,n2,n3) = crossover (p1,p2,n1,n3,n2)
by Th25;
hence
crossover (p1,p2,n1,n2,n3) = crossover (p1,p2,n3,n1,n2)
by Th25; verum