Metamath Proof Explorer


Theorem wrddm

Description: The indices of a word (i.e. its domain regarded as function) are elements of an open range of nonnegative integers (of length equal to the length of the word). (Contributed by AV, 2-May-2020)

Ref Expression
Assertion wrddm
|- ( W e. Word S -> dom W = ( 0 ..^ ( # ` W ) ) )

Proof

Step Hyp Ref Expression
1 wrdf
 |-  ( W e. Word S -> W : ( 0 ..^ ( # ` W ) ) --> S )
2 1 fdmd
 |-  ( W e. Word S -> dom W = ( 0 ..^ ( # ` W ) ) )