TOPICS
Search

Sister Celine's Method


A method for finding recurrence relations for hypergeometric polynomials directly from the series expansions of the polynomials. The method is effective and easily implemented, but usually slower than Zeilberger's algorithm. Given a sum f(n)=sum_(k)F(n,k), the method operates by finding a recurrence of the form

 sum_(i=0)^Isum_(j=0)^Ja_(ij)(n)F(n-j,k-i)=0

by proceeding as follows (Petkovšek et al. 1996, p. 59):

1. Fix trial values of I and J.

2. Assume a recurrence formula of the above form where a_(ij)(n) are to be solved for.

3. Divide each term of the assumed recurrence by F(n,k) and reduce every ratio F(n-j,k-i)/F(n,k) by simplifying the ratios of its constituent factorials so that only rational functions in n and k remain.

4. Put the resulting expression over a common denominator, then collect the numerator as a polynomial in k.

5. Solve the system of linear equations that results after setting the coefficients of each power of k in the numerator to 0 for the unknown coefficients a_(ij).

6. If no solution results, start again with larger I or J.

Under suitable hypotheses, a "fundamental theorem" (Verbaten 1974, Wilf and Zeilberger 1992, Petkovšek et al. 1996) guarantees that this algorithm always succeeds for large enough I and J (which can be estimated in advance). The theorem also generalizes to multivariate sums and to q- and multi-q-sums (Wilf and Zeilberger 1992, Petkovšek et al. 1996).


See also

Generalized Hypergeometric Function, Gosper's Algorithm, Hypergeometric Identity, Hypergeometric Series, Zeilberger's Algorithm

Explore with Wolfram|Alpha

References

Fasenmyer, Sister M. C. Some Generalized Hypergeometric Polynomials. Ph.D. thesis. University of Michigan, Nov. 1945.Fasenmyer, Sister M. C. "Some Generalized Hypergeometric Polynomials." Bull. Amer. Math. Soc. 53, 806-812, 1947.Fasenmyer, Sister M. C. "A Note on Pure Recurrence Relations." Amer. Math. Monthly 56, 14-17, 1949.Koepf, W. "Holonomic Recurrence Equations." Ch. 4 in Hypergeometric Summation: An Algorithmic Approach to Summation and Special Function Identities. Braunschweig, Germany: Vieweg, pp. 44-60, 1998.Petkovšek, M.; Wilf, H. S.; and Zeilberger, D. "Sister Celine's Method." Ch. 4 in A=B. Wellesley, MA: A K Peters, pp. 55-72, 1996. http://www.cis.upenn.edu/~wilf/AeqB.html.Rainville, E. D. Chs. 14 and 18 in Special Functions. New York: Chelsea, 1971.Verbaten, P. "The Automatic Construction of Pure Recurrence Relations." Proc. EUROSAM '74, ACM-SIGSAM Bull. 8, 96-98, 1974.Wilf, H. S. and Zeilberger, D. "An Algorithmic Proof Theory for Hypergeometric (Ordinary and "q") Multisum/Integral Identities." Invent. Math. 108, 575-633, 1992.

Referenced on Wolfram|Alpha

Sister Celine's Method

Cite this as:

Weisstein, Eric W. "Sister Celine's Method." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/SisterCelinesMethod.html

Subject classifications