Title :
The Conjectured Highest Scoring Machines for Rado´s Σ(k) for the Value k = 4
Author_Institution :
Department of Computing Science, University of Notre Dame, Notre Dame, Ind.
Abstract :
A study of the output of a heuristic computer program reveals two four-state binary Turing machines which yield the highest known score for four states in Rado\´s co-called "Busy Beaver" logical game. There is evidence which supports the conjecture that this score of 13 is the particular value of Σ(4), where Σ is a noncomputable integer function associated with this game. It is also conjectured that S(4) = 106, where S is another noncomputable function, the maximum shift number, of interest in Rado\´s study. Complete solution of the problem for four states has been reduced to a relatively small set of machines.
Keywords :
Adders; Algebra; Arithmetic; Concurrent computing; Diodes; Logic circuits; Signal generators; Switches; Turing machines; Upper bound;
Journal_Title :
Electronic Computers, IEEE Transactions on
DOI :
10.1109/PGEC.1966.264572