let n1, n2, n3 be Element of NAT ; :: thesis: for S being Gene-Set
for p1, p2 being Individual of S holds crossover (p1,p2,n1,n2,n3) is Individual of S
let S be Gene-Set; :: thesis: for p1, p2 being Individual of S holds crossover (p1,p2,n1,n2,n3) is Individual of S
let p1, p2 be Individual of S; :: thesis: crossover (p1,p2,n1,n2,n3) is Individual of S
reconsider q1 = crossover (p1,p2,n1,n2), q2 = crossover (p2,p1,n1,n2) as Individual of S ;
crossover (q1,q2,n3) is Individual of S ;
hence crossover (p1,p2,n1,n2,n3) is Individual of S ; :: thesis: verum