Sudan function
The Sudan is a recursive function computable function, the μ - recursive but not primitive recursive totally what it has in common with the better-known Ackermann function.
It was published in 1927 by the Romanian mathematician Gabriel Sudan, as Wilhelm Ackermann was a student of David Hilbert.
Definition
For the following applies:
Background
1926 David Hilbert conjectured that every computable function is primitive recursive. This was achieved by Wilhelm Ackermann and Gabriel Sudan - were published by different functions in a timely manner (Sudan in 1927 and Ackermann 1928), refuted - both his students. The Sudan function and the Ackermann function so were the first published, not primitive recursive functions.