Metamath Proof Explorer


Theorem divalgmodcl

Description: The result of the mod operator satisfies the requirements for the remainder R in the division algorithm for a positive divisor. Variant of divalgmod . (Contributed by Stefan O'Rear, 17-Oct-2014) (Proof shortened by AV, 21-Aug-2021)

Ref Expression
Assertion divalgmodcl
|- ( ( N e. ZZ /\ D e. NN /\ R e. NN0 ) -> ( R = ( N mod D ) <-> ( R < D /\ D || ( N - R ) ) ) )

Proof

Step Hyp Ref Expression
1 divalgmod
 |-  ( ( N e. ZZ /\ D e. NN ) -> ( R = ( N mod D ) <-> ( R e. NN0 /\ ( R < D /\ D || ( N - R ) ) ) ) )
2 1 baibd
 |-  ( ( ( N e. ZZ /\ D e. NN ) /\ R e. NN0 ) -> ( R = ( N mod D ) <-> ( R < D /\ D || ( N - R ) ) ) )
3 2 3impa
 |-  ( ( N e. ZZ /\ D e. NN /\ R e. NN0 ) -> ( R = ( N mod D ) <-> ( R < D /\ D || ( N - R ) ) ) )