Abstract: In
this paper, we consider a second order three-point differential operator L
in determined by the formal
differential expression and by the boundary conditions
For the solutions u
and v of the differential equation such that and asymptotic formulas are established
on the horizontal strip for Then we establish an asymptotic
formula for the characteristic determinant of L
on
Keywords and phrases: three-point differential operator, asymptotic expansion, characteristic determinant.
