theorem Th6: :: OSAFREE:6

for S being OrderSortedSign
for X being non-empty ManySortedSet of S
for o being OperSymbol of S
for p being FinSequence of TS (DTConOSA X) holds
( p in (((ParsedTerms X) #) * the Arity of S) . o iff ( dom p = dom (the_arity_of o) & ( for n being Nat st n in dom p holds
p . n in ParsedTerms (X,((the_arity_of o) /. n)) ) ) )