Resolution of the Final ODE

We use the gfun package to solve for the solution [Maple Math] which corresponds to the integral to be computed. Due to its integral representation, this function is analytic at 0, hence admits a Taylor expansion at 0. We proceed to compute a closed form for [Maple Math] by summation of this expansion. To this end, we determine a recurrence equation on the coefficients of the Taylor expansion using gfun[diffeqtorec] :

> [Maple Math]

[Maple Math]

Maple readily solves this recurrence:

> rsol:=rsolve(ore,u(n));

[Maple Math]
[Maple Math]

After rearranging the terms in the sum, it is obvious that [Maple Math] is non-zero for even [Maple Math] only.

> collect(map(normal,rsol,expanded),u,factor);

[Maple Math]

We perform the corresponding change of variable, [Maple Math] ,

> subs({n=2*p,(-1)^n=1,RootOf(_Z^2+1)^n=(-1)^p},");

[Maple Math]

so that Maple can sum the Taylor series:

> sum("*a^(2*p),p=0..infinity);

[Maple Math]

> h:=collect(value(expand(")),u);

[Maple Math]

It only remains to evaluate [Maple Math] and [Maple Math] . We first compute [Maple Math] and find it is 0 by inversion of limits. Let

> [Maple Math]

be the integrand. We have:

> [Maple Math]

[Maple Math]

In the same way, each coefficient of the Taylor series for the integral is obtained by inversion of limits. In particular, [Maple Math] , but Maple is not capable of integrating:

> kappa=int(coeff(series(normal(diff(f,a,a)),a=0),a,0)/2,x=0..infinity);

[Maple Math]

(This integral for [Maple Math] cannot be computed by a call to int using the Release 4, but the next release will probably be able to integrate it.)

We obtain the following form for [Maple Math] :

> -combine(normal(-subs({u(0)=0,u(2)=kappa},h)),ln,symbolic);

[Maple Math]

It only remains to be proved that [Maple Math] . We do not do it, since computing this last integral which is a constant lies outside the scope of the theory of holonomy. With this example, we have reduced the problem of evaluating a parametrized integral to the evaluation of a non-parametrized integral. In case there were no closed form for [Maple Math] , we could at least perform a simple numerical evaluation and return a result in terms of this numerical value and the series above for [Maple Math] .