Metamath Proof Explorer


Theorem gcdcllem2

Description: Lemma for gcdn0cl , gcddvds and dvdslegcd . (Contributed by Paul Chapman, 21-Mar-2011)

Ref Expression
Hypotheses gcdcllem2.1 S=z|nMNzn
gcdcllem2.2 R=z|zMzN
Assertion gcdcllem2 MNR=S

Proof

Step Hyp Ref Expression
1 gcdcllem2.1 S=z|nMNzn
2 gcdcllem2.2 R=z|zMzN
3 breq1 z=xzMxM
4 breq1 z=xzNxN
5 3 4 anbi12d z=xzMzNxMxN
6 5 2 elrab2 xRxxMxN
7 breq1 z=xznxn
8 7 ralbidv z=xnMNznnMNxn
9 8 1 elrab2 xSxnMNxn
10 breq2 n=MxnxM
11 breq2 n=NxnxN
12 10 11 ralprg MNnMNxnxMxN
13 12 anbi2d MNxnMNxnxxMxN
14 9 13 bitrid MNxSxxMxN
15 6 14 bitr4id MNxRxS
16 15 eqrdv MNR=S