let n, m, n1, m1, n2, m2 be natural number ; :: thesis: ( n1 in NatDivisors n & m1 in NatDivisors m & n2 in NatDivisors n & m2 in NatDivisors m & n,m are_relative_prime & n1 * m1 = n2 * m2 implies ( n1 = n2 & m1 = m2 ) )
assume A1: n1 in NatDivisors n ; :: thesis: ( not m1 in NatDivisors m or not n2 in NatDivisors n or not m2 in NatDivisors m or not n,m are_relative_prime or not n1 * m1 = n2 * m2 or ( n1 = n2 & m1 = m2 ) )
then A2: ( 0 < n1 & n1 divides n ) by MOEBIUS1:39;
assume A3: m1 in NatDivisors m ; :: thesis: ( not n2 in NatDivisors n or not m2 in NatDivisors m or not n,m are_relative_prime or not n1 * m1 = n2 * m2 or ( n1 = n2 & m1 = m2 ) )
then A4: ( 0 < m1 & m1 divides m ) by MOEBIUS1:39;
assume A5: n2 in NatDivisors n ; :: thesis: ( not m2 in NatDivisors m or not n,m are_relative_prime or not n1 * m1 = n2 * m2 or ( n1 = n2 & m1 = m2 ) )
then A6: ( 0 < n2 & n2 divides n ) by MOEBIUS1:39;
assume A7: m2 in NatDivisors m ; :: thesis: ( not n,m are_relative_prime or not n1 * m1 = n2 * m2 or ( n1 = n2 & m1 = m2 ) )
then A8: ( 0 < m2 & m2 divides m ) by MOEBIUS1:39;
assume A9: n,m are_relative_prime ; :: thesis: ( not n1 * m1 = n2 * m2 or ( n1 = n2 & m1 = m2 ) )
assume A10: n1 * m1 = n2 * m2 ; :: thesis: ( n1 = n2 & m1 = m2 )
assume A11: ( not n1 = n2 or not m1 = m2 ) ; :: thesis: contradiction
now
assume A12: n1 <> n2 ; :: thesis: contradiction
reconsider n1' = n1, n2' = n2 as non empty Nat by A1, A5, MOEBIUS1:39;
reconsider m1' = m1, m2' = m2 as non empty Nat by A3, A7, MOEBIUS1:39;
consider p being Element of NAT such that
A13: ( p is prime & p |-count n1' <> p |-count n2' ) by A12, NAT_4:21;
reconsider p = p as Prime by A13;
A14: (p |-count n1') + (p |-count m1') = p |-count (n1' * m1') by NAT_3:28
.= (p |-count n2') + (p |-count m2') by A10, NAT_3:28 ;
( p |-count m1' <> 0 or p |-count m2' <> 0 ) by A13, A14;
then ( p divides m1' or p divides m2' ) by MOEBIUS1:6;
then A15: p divides m by A4, A8, INT_2:13;
( p |-count n1' <> 0 or p |-count n2' <> 0 ) by A13;
then ( p divides n1' or p divides n2' ) by MOEBIUS1:6;
then A16: p divides n by A2, A6, INT_2:13;
A17: n gcd m > 0 by A9, INT_2:def 4;
p divides n gcd m by A15, A16, INT_2:def 3;
then A18: p <= n gcd m by A17, INT_2:43;
p > 1 by INT_2:def 5;
hence contradiction by A18, A9, INT_2:def 4; :: thesis: verum
end;
hence contradiction by A10, A11, A6, XCMPLX_1:5; :: thesis: verum