statistical function
To each constructive object corresponds a function of a natural number k—the log of minimal cardinality of x-containing sets that allow definitions of complexity at most k. If the element x itself allows a simple definition, then the function drops to 0 even for small k. Lacking such definition, the element is "random" in a negative sense. But it is positively "probabilistically random" only when function having taken the value at a relatively small , then changes approximately as .
Kolmogorov structure function
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