ExponentialGeneratingFunction [expr,n,x]
gives the exponential generating function in x for the sequence whose n^(th) term is given by the expression expr.
ExponentialGeneratingFunction [expr,{n1,n2,…},{x1,x2,…}]
gives the multidimensional exponential generating function in x1, x2, … whose n1, n2, … term is given by expr.
ExponentialGeneratingFunction
ExponentialGeneratingFunction [expr,n,x]
gives the exponential generating function in x for the sequence whose n^(th) term is given by the expression expr.
ExponentialGeneratingFunction [expr,{n1,n2,…},{x1,x2,…}]
gives the multidimensional exponential generating function in x1, x2, … whose n1, n2, … term is given by expr.
Details and Options
- The exponential generating function for a sequence whose ^(th) term is is given by .
- The multidimensional exponential generating function is given by .
- The following options can be given:
-
Examples
open all close allBasic Examples (1)
The exponential generating function for the sequence whose n^(th) term is 1:
The ^(th) term in the series is :
Scope (19)
Basic Uses (6)
Exponential generating function of a univariate sequence:
Exponential generating function of a multivariate sequence:
Compute a typical exponential generating function:
Plot the magnitude using Plot3D , ContourPlot or DensityPlot :
Plot the complex phase:
Generate conditions for the region of convergence:
Plot the region for :
Evaluate the exponential generating function at a point:
Plot the spectrum:
The phase:
Plot both the spectrum and the plot phase using color:
Plot the spectrum in the complex plane using ParametricPlot3D :
ExponentialGeneratingFunction will use several properties including linearity:
Multiplication by exponentials:
Multiplication by polynomials:
Conjugate:
ExponentialGeneratingFunction automatically threads over lists:
Equations:
Rules:
Special Sequences (13)
Discrete unit steps:
Discrete ramps:
Polynomials:
Factorial polynomials:
Exponential functions:
Exponential polynomials:
Factorial exponential polynomials:
Trigonometric functions:
Trigonometric, exponential and polynomial:
Combinations of the previous input:
Different ways of expressing piecewise-defined signals:
Rational functions:
Rational exponential functions:
Hypergeometric term sequences:
The DiscreteRatio is rational for all hypergeometric term sequences:
Many functions give hypergeometric terms:
Any products are hypergeometric terms:
Transforms of hypergeometric terms:
Holonomic sequences:
A holonomic sequence is defined by a linear difference equation:
Many special function are holonomic sequences in their index:
DifferenceRoot in general results in DifferentialRoot functions:
Special sequences:
Periodic sequences:
Multivariate exponential generating functions:
Generalizations & Extensions (1)
Compute the exponential generating function at a point:
Options (5)
GenerateConditions (1)
By default, no conditions are given for where a generating function is convergent:
Use GenerateConditions to generate conditions of validity:
Method (1)
Different methods may produce different formulas:
VerifyConvergence (3)
Setting VerifyConvergence to False will treat generating functions as formal objects:
Setting VerifyConvergence to True will verify that the radius of convergence is nonzero:
In addition, setting GenerateConditions to True will display the conditions for convergence:
Properties & Relations (3)
ExponentialGeneratingFunction effectively computes an infinite sum:
Linearity:
ExponentialGeneratingFunction is closely related to GeneratingFunction :
Possible Issues (1)
A ExponentialGeneratingFunction may not converge for all values of parameters:
Use GenerateConditions to get the region of convergence:
Neat Examples (1)
Create a gallery of exponential generating functions:
Related Guides
History
Text
Wolfram Research (2008), ExponentialGeneratingFunction, Wolfram Language function, https://reference.wolfram.com/language/ref/ExponentialGeneratingFunction.html.
CMS
Wolfram Language. 2008. "ExponentialGeneratingFunction." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/ExponentialGeneratingFunction.html.
APA
Wolfram Language. (2008). ExponentialGeneratingFunction. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/ExponentialGeneratingFunction.html
BibTeX
@misc{reference.wolfram_2025_exponentialgeneratingfunction, author="Wolfram Research", title="{ExponentialGeneratingFunction}", year="2008", howpublished="\url{https://reference.wolfram.com/language/ref/ExponentialGeneratingFunction.html}", note=[Accessed: 16-November-2025]}
BibLaTeX
@online{reference.wolfram_2025_exponentialgeneratingfunction, organization={Wolfram Research}, title={ExponentialGeneratingFunction}, year={2008}, url={https://reference.wolfram.com/language/ref/ExponentialGeneratingFunction.html}, note=[Accessed: 16-November-2025]}