let i be Nat; :: thesis: for D, D9, E being non empty set
for d9 being Element of D9
for F being Function of [:D,D9:],E
for z being Tuple of i,D holds F [:] z,d9 is Element of i -tuples_on E
let D, D9, E be non empty set ; :: thesis: for d9 being Element of D9
for F being Function of [:D,D9:],E
for z being Tuple of i,D holds F [:] z,d9 is Element of i -tuples_on E
let d9 be Element of D9; :: thesis: for F being Function of [:D,D9:],E
for z being Tuple of i,D holds F [:] z,d9 is Element of i -tuples_on E
let F be Function of [:D,D9:],E; :: thesis: for z being Tuple of i,D holds F [:] z,d9 is Element of i -tuples_on E
let z be Tuple of i,D; :: thesis: F [:] z,d9 is Element of i -tuples_on E
reconsider r = F [:] z,d9 as FinSequence of E by Th97;
len z = i by FINSEQ_1:def 18;
then len r = i by Th98;
hence F [:] z,d9 is Element of i -tuples_on E by Th110; :: thesis: verum