Code and Data

J. Han, K. Lee, L. Li, N. Loehr, Chain decompositions of q, t-catalan numbers via local chains, https://arxiv.org/abs/2003.03896

  • Here is the Extended Appendix.

  • In this folder you can find the SageMath code to check that our global chains indeed satisfy the desired properties. To run it, put files "k=1.txt",...,"k=11.txt" to the appropriate folder, and paste the code in "main_code.txt" to a Sage cell. The output is in "outpu.txt".

K. Lee, L. Li, N. Loehr, A Combinatorial Approach to the Symmetry of $q,t$-Catalan Numbers, SIAM J. Discrete Math (SIDMA). 32 (2018) no.1, 191--232.

SageMath is a free open-source mathematics software system, which can be downloaded here. You may also try the online version CoCalc (SageMathCloud).

  • First input this code and you will see this output. It defines relevant functions in the paper and computes some examples in the paper.

  • Run this this code, and you will see this output. It shows that there is a unique solution of Conjecture 4.8 for k<=4 and two solutions for k=5.

  • Run this this code, and you will see this output. It finds a solution for k=6.

  • List_of_C_mu.pdf (previously available in www.oakland.edu/~li2345/List_of_C_mu.pdf as stated in section 6 of the paper)

  • Run this code. Then run code(k=7), code(k=8), code(k=9). It checks that the solutions for k=7,8,9 given in the above pdf file satisfy Conjecture 4.8.

Higher (Haiman/Hagland)-Catalan numbers

It is conjectured that the higher q,t-Catalan number C^m_n(q,t) defined by Garsia and Haiman coincides with the combinatorially defined (Haiman/Haglund-)Catalan number. (cf. N.Loehr's paper "Conjectured Statistics for the Higher q,t-Catalan Sequences"). Here is a list of Catalan numbers, q-Catalan numbers and higher q,t-Catalan numbers.