Metamath Proof Explorer


Theorem fsuppmapnn0fz

Description: If a function over the nonnegative integers is finitely supported, then there is an upper bound for a finite set of sequential integers containing the support of the function. (Contributed by AV, 30-Sep-2019) (Proof shortened by AV, 6-Oct-2019)

Ref Expression
Assertion fsuppmapnn0fz FR0ZVfinSuppZFm0FsuppZ0m

Proof

Step Hyp Ref Expression
1 fsuppmapnn0ub FR0ZVfinSuppZFm0x0m<xFx=Z
2 simpllr FR0ZVm0x0m<xFx=ZZV
3 simplll FR0ZVm0x0m<xFx=ZFR0
4 simplr FR0ZVm0x0m<xFx=Zm0
5 simpr FR0ZVm0x0m<xFx=Zx0m<xFx=Z
6 2 3 4 5 suppssfz FR0ZVm0x0m<xFx=ZFsuppZ0m
7 6 ex FR0ZVm0x0m<xFx=ZFsuppZ0m
8 7 reximdva FR0ZVm0x0m<xFx=Zm0FsuppZ0m
9 1 8 syld FR0ZVfinSuppZFm0FsuppZ0m