Turing Machines
[25/96%]Which function is computed by the machine with the following program of commands:
Let the machine have the following program:
Which functions does this machine compute?
Construct a Turing machine that correctly computes the function .
Construct a Turing machine that correctly computes the function .
Construct the following Turing machines:
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Zero transfer: .
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Right shift: .
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Left shift: .
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Transposition: .
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Doubling: .
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Cyclic shift: .
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Copying: .
Construct a Turing machine that correctly computes the function (where ).
Let the functions and be correctly Turing computable. Show that the function is correctly Turing computable.
Let the functions and be correctly Turing computable. Show that the function is correctly Turing computable.
Construct a Turing machine for the correct computation of the functions:
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Prove that:
if the function is obtained from correctly Turing computable functions and by means of primitive recursion, then is correctly Turing computable;
if the function is obtained from a correctly Turing computable function by means of the -operator, then is correctly Turing computable.
Prove that every partial recursive function is correctly Turing computable.
Prove that there exist primitive recursive functions such that:
, if and ;
for some machine that transforms the word into the word ;
, if , , .
Construct primitive recursive functions such that
Construct a primitive recursive function satisfying the condition: if , , , then , where is for , for , for .
Construct a primitive recursive function satisfying the condition: if , , , occurs in the alphabet of internal states, and in the external alphabet of the machine , then .
Construct a primitive recursive function satisfying the condition: if , , where is a machine word in the alphabet of the machine , then .
Construct a primitive recursive function satisfying the condition: if , , where is a machine word in the alphabet of the machine , then .
Construct a primitive recursive function satisfying the condition: if , then is the number of occurrences of the symbol in the word .
Prove that if the machine computes and , then:
for some ;
, where , and the functions , and are taken from problems III.2.12, III.2.16, and III.2.17.
Prove that every Turing computable function is partial recursive.
Prove that a function is Turing computable if and only if there is a Turing machine with external alphabet computing this function.
Prove that there exists a two-place partial recursive function universal for the family of all one-place partial recursive functions.
Prove that there exists an -place partial recursive function universal for the family of all -ary partial recursive functions.
Prove that the following functions are not partial recursive:
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Prove that there exists a primitive recursive function such that
Prove that there exist primitive recursive functions such that:
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