.
"(Linguistics"@en .
"Linguistics"@en .
.
"Grammars"@en .
.
"vau" .
"New proofs of old theorems in logic and formal linguistics."@en .
"NOV 1966" .
.
.
.
.
.
"en" .
"1966" .
.
.
.
"Theorem 1 constructs, from any word problem in a semi-Thue system, an equivalent Post correspondence problem, showing the undecidability of the general Post correspondence problem. Theorem 2 constructs, from any Post correspondence problem, a minimal linear grammar which is ambiguous exactly if the Post correspondence problem has a solution, showing the undecidability of the general ambiguity problem. (Other standard undecidability results on phrase structure grammars are implied.) Theorem 3 constructs, from any word problem in a semi-Thue system, an ambiguity problem, combining the results of Theorem 1 and 2 by more direct means. No new results are presented, but standard proofs were shortened and constructions eliminated, combined, or simplified. (Author)."@en .
.
"227469361" .
.
.
.
.
"227469361" .
.
.
"CARNEGIE INST OF TECH PITTSBURGH PA." .
.
"Ft. Belvoir" .
.
.
.
"NOV 1966" .
.
"Theorems)"@en .
.
"Defense Technical Information Center" .
.
"Floyd" .
"Robert W." .
"Robert W. Floyd" .
.
.
.
"2016-07-10" .
.