Difference equations: disconjugacy, principal solutions, Green’s functions, complete monotonicity

We find analogues of known results on nth order linear differen- tial equations for nth order linear difference equations. These include the concept of disconjugacy, P6lya's criterion for disconjugacy, Frobenius fac- torizations, generalized Sturm theorems, existence and properties of prin- cipal solutions, signs of Green's functions, and completely monotone fami- lies of solutions of equations depending on a parameter.

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