论文信息 - Permutations Sortable by n – 4 Passes Through a Stack

Permutations Sortable by n – 4 Passes Through a Stack

We characterise and enumerate permutations that are sortable by n – 4 passes through a stack. We conjecture the number of permutations sortable by n – 5 passes, and also the form of a formula for the general case n – k, which involves a polynomial expression.

[1] Einar Steingrimsson,et al. Generalized permutation patterns - a short survey , 2008, 0801.2412.

[2] Donald E. Knuth. The art of computer programming: fundamental algorithms , 1969 .

[3] Julian West,et al. Permutations with forbidden subsequences, and, stack-sortable permutations , 1990 .

[4] Donald Ervin Knuth,et al. The Art of Computer Programming , 1968 .

[5] Donald E. Knuth,et al. The art of computer programming: V.1.: Fundamental algorithms , 1997 .