let n1, n3, n2 be Element of NAT ; for S being Gene-Set
for p1, p2 being Individual of S st n1 >= len p1 & n3 >= len p1 holds
crossover p1,p2,n1,n2,n3 = crossover p1,p2,n2
let S be Gene-Set; for p1, p2 being Individual of S st n1 >= len p1 & n3 >= len p1 holds
crossover p1,p2,n1,n2,n3 = crossover p1,p2,n2
let p1, p2 be Individual of S; ( n1 >= len p1 & n3 >= len p1 implies crossover p1,p2,n1,n2,n3 = crossover p1,p2,n2 )
assume that
A1:
n1 >= len p1
and
A2:
n3 >= len p1
; crossover p1,p2,n1,n2,n3 = crossover p1,p2,n2
crossover p1,p2,n1,n2,n3 = crossover p1,p2,n2,n3
by A1, Th18;
hence
crossover p1,p2,n1,n2,n3 = crossover p1,p2,n2
by A2, Th10; verum