The Ackermann and Sudan functions are chronologically the first examples of recursive functions which are not primitive recursive .
Sudan constructed the function that bears his name with the same aim as Wilhelm Ackermann : to solve in the affirmative a problem raised by Hilbert .
The Wilhelm Ackermann and Sudan functions are chronologically the first examples of recursive functions which are not primitive recursive .
Sudan constructed the function that bears his name with the same aim as Wilhelm Ackermann : to solve in the affirmative a problem raised by Hilbert .