Skip to main content
Log in

Enumeration and Generating Functions of Rota–Baxter Words

  • Published:
Mathematics in Computer Science Aims and scope Submit manuscript

Abstract

In this paper, we prove results on enumerations of sets of Rota–Baxter words (\({{{\tt RBWs}}}\)) in a single generator and one unary operator. Examples of operators are integral operators, their generalization to Rota–Baxter operators, and Rota–Baxter type operators. \({{{\tt RBWs}}}\) are certain words formed by concatenating generators and images of words under the operators. Under suitable conditions, they form canonical bases of free Rota–Baxter type algebras which are studied recently in relation to renormalization in quantum field theory, combinatorics, number theory, and operads. Enumeration of a basis is often a first step to choosing a data representation in implementation. We settle the case of one generator and one operator, starting with the idempotent case (more precisely, the exponent 1 case). Some integer sequences related to these sets of \({{{\tt RBWs}}}\) are known and connected to other sequences from combinatorics, such as the Catalan numbers, and others are new. The recurrences satisfied by the generating series of these sequences prompt us to discover an efficient algorithm to enumerate the canonical basis of certain free Rota–Baxter algebras.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Aguiar M.: Prepoisson algebras. Lett. Math. Phys. 54(4), 263–277 (2000)

    Article  MATH  MathSciNet  Google Scholar 

  2. Aguiar, M., Moreira, W.: Combinatorics of the free Baxter algebra. J. Combin. 13(1) (2006) (research paper 17, p. 38) (electronic)

  3. Aho, A.V., Ullman, J.D.: The Theory of Parsing, Translation, and Compiling, vol. 1. Parsing. Prentice Hall, Englewood Cliffs (1972)

  4. Baxter G.: An analytic problem whose solution follows from a simple algebraic identity. Pac. J. Math. 10(3), 731–742 (1960)

    MATH  MathSciNet  Google Scholar 

  5. Bokut L.A., Chen Y., Qiu J.: Gröbner–Shirshov bases for associative algebras with multiple operators and free Rota–Baxter algebras. J. Pure Appl. Algebra 214(1), 89–100 (2010)

    Article  MATH  MathSciNet  Google Scholar 

  6. Cartier P.: On the structure of free Baxter algebras. Adv. Math. 9, 253–265 (1972)

    Article  MATH  MathSciNet  Google Scholar 

  7. Chen K.T., Fox R.H., Lyndon R.C.: Free differential calculus, IV. The quotient groups of the lower central series. Ann. Math. 68, 81–95 (1958)

    Article  MathSciNet  Google Scholar 

  8. Connes A., Kreimer D.: Renormalization in quantum field theory and the Riemann–Hilbert problem. I. The Hopf algebra structure of graphs and the main theorem. Comm. Math. Phys. 210(1), 249–273 (2000)

    Article  MATH  MathSciNet  Google Scholar 

  9. Connes A., Kreimer D.: Renormalization in quantum field theory and the Riemann–Hilbert problem. II. The β-function, diffeomorphisms and the renormalization group. Comm. Math. Phys. 216(1), 215–241 (2001)

    Article  MATH  MathSciNet  Google Scholar 

  10. Ebrahimi-Fard K.: Loday-type algebras and the Rota–Baxter relation. Lett. Math. Phys. 61(2), 139–147 (2002)

    Article  MATH  MathSciNet  Google Scholar 

  11. Ebrahimi-Fard K., Guo L.: Rota–Baxter algebras and dendriform algebras. J. Pure Appl. Algebra 212, 320–339 (2008)

    Article  MATH  MathSciNet  Google Scholar 

  12. Ebrahimi-Fard K., Guo L.: Free Rota–Baxter algebras and rooted trees. J. Algebra Appl. 7(2), 167–194 (2008)

    Article  MATH  MathSciNet  Google Scholar 

  13. Ebrahimi-Fard K., Guo L., Kreimer D.: Spitzer’s identity and the algebraic Birkhoff decomposition in pQFT. J. Phys. A Math. Gen. 37(45), 11037–11052 (2004)

    Article  MATH  MathSciNet  Google Scholar 

  14. Ebrahimi-Fard K., Guo L., Kreimer D.: Integrable renormalization II: the general case. Ann. Henri Poincaré 6(2), 369–395 (2005)

    Article  MATH  MathSciNet  Google Scholar 

  15. Ebrahimi-Fard K., Gracia-Bonda J.M., Patras F.: Rota–Baxter algebras and new combinatorial identities. Lett. Math. Phys. 81(1), 61–75 (2007)

    Article  MATH  MathSciNet  Google Scholar 

  16. Ebrahimi-Fard K., Manchon D., Patras F.: A noncommutative Bohnenblust–Spitzer identity for Rota–Baxter algebras solves Bogoliubov’s recursion. J. Noncommut. Geom. 3(2), 181–222 (2009)

    Article  MATH  MathSciNet  Google Scholar 

  17. Flajolet, P., Salvy, B.: Computer algebra libraries for combinatorial structures. J. Symbolic Comput. 20(5–6), 653–671 (1995). http://algo.inria.fr/libraries/

    Google Scholar 

  18. Guo L.: Baxter algebras, Stirling numbers and partitions. J. Algebra Appl. 4, 153–164 (2005)

    Article  MATH  MathSciNet  Google Scholar 

  19. Guo L.: Operated semigroups, Motzkin paths and rooted trees. J. Algebraic Combin. 29(1), 35–62 (2009)

    Article  MATH  MathSciNet  Google Scholar 

  20. Guo L., Keigher W.: Baxter algebras and shuffle products. Adv. Math. 150(1), 117–149 (2000)

    Article  MATH  MathSciNet  Google Scholar 

  21. Guo L., Keigher W.: On free Baxter algebras: completions and the internal construction. Adv. Math. 151(1), 101–127 (2000)

    Article  MATH  MathSciNet  Google Scholar 

  22. Guo L., Keigher W.: On differential Rota–Baxter algebras. J. Pure Appl. Algebra 212(3), 522–540 (2008)

    Article  MATH  MathSciNet  Google Scholar 

  23. Guo, L., Sit, W.: Enumeration of Rota–Baxter words (extended abstract). In: Proceedings ISSAC 2006, Genoa, Italy, pp. 124–131. ACM Press, New York (2006)

  24. Guo, L., Sit, W.: Enumeration and generating functions of differential Rota–Baxter words. In: Regensburger, G., Rosenkranz, M., Sit, W.Y. (eds.) Algebraic and Algorithmic Aspects of Differential and Integral Operators (AADIOS), Math. Comp. Sci., vol. 4, Sp. Issue (2,3) (2011) (special issue). doi:10.1007/s11786-010-0062-1

  25. Kuroš A.G.: Non-associative free algebras and free products of algebras (in Russian, English summary). Rec. Math. [Math. Sbornik] N. S. 20(62), 239–262 (1947)

    Google Scholar 

  26. Kuroš A.G.: Free sums of multiple operator algebras (in Russian). Sibirsk. Mat. Ž 1, 62–70 (1960) (correction 638)

    MathSciNet  Google Scholar 

  27. Loday J.-L. et al.: Dialgebras. In: Loday, J.-L. (eds) Dialgebras and Related Operads Lecture. Notes in Mathematics, vol. 1763, pp. 7–66. Springer, Berlin (2001)

    Chapter  Google Scholar 

  28. Loday J.-L., Ronco M.: On the structure of cofree Hopf algebras. J. Reine Angew. Math. 592, 123–155 (2006)

    Article  MATH  MathSciNet  Google Scholar 

  29. MacMahon M.P.A.: Combinatory Analysis, 3rd edn. Chelsea Publishing Company, New York (1984)

    Google Scholar 

  30. Melançon G., Reutenauer C.: Lyndon words, free algebras and shuffles. Can. J. Math. 41(4), 577–591 (1989)

    Article  MATH  Google Scholar 

  31. Nijenhuis A., Wilf H.: Combinatorial algorithms, 2nd edn. Academic Press, New York (1978)

    MATH  Google Scholar 

  32. Rosenkranz M., Regensburger G.: Solving and factoring boundary problems for linear ordinary differential equations in differential algebra. J. Symbolic Comput. 43(8), 515–544 (2008)

    Article  MATH  MathSciNet  Google Scholar 

  33. Rota, G.-C.: Baxter algebras and combinatorial identities I, II. Bull. Am. Math. Soc. 75, 325–329, 330–334 (1969)

    Google Scholar 

  34. Rota, G.-C.: Baxter operators, an introduction. In: Kung, J.P.S. (ed.) Gian-Carlo Rota on Combinatorics, Introductory Papers and Commentaries, pp. 504–512. Contemporary Mathematicians, Birkhäuser (1995)

  35. Rota, G.-C., Smith, D.A.: Fluctuation theory and Baxter algebras. Symposia Mathematica, IX (Convegno di Calcolo delle Probabilità, INDAM, Rome, 1971), pp. 179–201. Academic Press, New York (1972)

  36. Sloane, N. et al.: On-Line Encyclopedia of Integer Seqences. http://www.research.att.com/~njas/sequences/index.html (2010)

  37. Shirshov A.I.: Some algorithmic problem for \(\epsilon\) -algebras (in Russian). Sibirsk. Mat. Z. 3, 132–137 (1962)

    MATH  MathSciNet  Google Scholar 

  38. Shirshov, A.I.: Some algorithmic problem for Lie algebras (in Russian). Sibirsk. Mat. Z. 3, 292–296 (1962) (English translation: SIGSAM Bull. 33(2), 3–6 (1999))

  39. Zhukov A.I.: Reduced systems of defining relations in non-associative algebras (in Russian). Mat. Sbornik 69(27), 267–280 (1950)

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to William Y. Sit.

Additional information

Li Guo acknowledges support from NSF grants DMS 0505643 and DMS 1001855.

William Sit acknowledges support from NSF grant CCF-0430722.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Guo, L., Sit, W.Y. Enumeration and Generating Functions of Rota–Baxter Words. Math.Comput.Sci. 4, 313–337 (2010). https://doi.org/10.1007/s11786-010-0061-2

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11786-010-0061-2

Keywords

Mathematics Subject Classification (2010)

Navigation