Finds all solutions of the linear recurrence equation with constant coefficients.

Optionally, one can specify output=basis  or output=gensol, which specifies respectively that one wants a basis of the solutions or a generic solution.  The initial conditions that may be associated to the problem are only used in the generic solution case.  Arbitrary constants for the basis case are represented as _C[1], _C[2], ..., _C[n], where the _C is an escaped local variable.

See the help page for LREtools[REcreate] for the definition of the format of a problem.