12 citations · 38 across the 15 of their papers we have counts for
4 papers · 1 filter
Extreme Palindromes
Kathy Q. Ji, Herbert S. Wilf
A recursively palindromic (RP) word is one that is a palindrome and whose left half-word and right half-word are each RP. Thus ABACABA is, and MADAM is not, an RP word. We count RP…
Computing the distribution of the maximum in balls-and-boxes problems, with application to clusters of disease cases
Warren J. Ewens, Herbert S. Wilf
We present a rapid method for the exact calculation of the cumulative distribution function of the maximum of multinomially distributed random variables. The method runs in time $O…
Counting permutations by their runs up and down
E. Rodney Canfield, Herbert S. Wilf
We find a formula for the number of permutations of that have exactly runs up and down. The formula is at once terminating, asymptotic, and exact.
BG-ranks and 2-cores
William Y. C. Chen, Kathy Q. Ji, Herbert S. Wilf
We find the number of partitions of whose BG-rank is , in terms of , the number of pairs of partitions whose total number of cells is , giving both bijective and g…