We consider the reduction of the degenerate difference-differential equations with Fredholm operator in the main expression to the regular problems. It is shown how the question of the choice of boundary conditions is connected with the Jordan structure of operator coefficients of the equations. The problem of the choice of boundary conditions is solved. The theorems of existence and uniqueness of boundary value problems are proved. The abstract theorems are used for statement and investigation of boundary value problems for partial differential equations and difference equations with degeneration.

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