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A350426 a(n) is the maximum number of key comparisons required to sort n records with distinct keys using heapsort (Algorithm H in Don Knuth's TAOCP Vol. 3). 3
1, 3, 7, 12, 17, 22, 29, 37, 44, 51, 59, 66, 73, 80 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,2
COMMENTS
There are two places in the algorithm where the keys are compared. The first is in step H4 [Find larger child] and the second in step H6 [Larger than K?]. The sequence shows the maxima of the counts of these comparisons, determined over all n! possible orders of the records.
a(16) >= 90.
REFERENCES
D. E. Knuth, The Art of Computer Programming Second Edition. Vol. 3, Sorting and Searching. Chapter 5.2.3 Sorting by Selection, Page 145. Addison-Wesley, Reading, MA, 1998.
LINKS
CROSSREFS
A350569 contains a table with the maximum and average number of comparisons for the original algorithm and for its modified version.
Sequence in context: A192740 A310246 A310247 * A332263 A310248 A298022
KEYWORD
nonn,more
AUTHOR
Hugo Pfoertner, Jan 05 2022
STATUS
approved

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Last modified April 17 08:54 EDT 2024. Contains 371763 sequences. (Running on oeis4.)