Metamath Proof Explorer


Theorem ndvdsp1

Description: Special case of ndvdsadd . If an integer D greater than 1 divides N , it does not divide N + 1 . (Contributed by Paul Chapman, 31-Mar-2011)

Ref Expression
Assertion ndvdsp1 ND1<DDN¬DN+1

Proof

Step Hyp Ref Expression
1 1nn 1
2 1 jctl 1<D11<D
3 ndvdsadd ND11<DDN¬DN+1
4 2 3 syl3an3 ND1<DDN¬DN+1