Several asymptotic expansions and formulas for cubic exponential sums are derived. The expansions are most useful when the cubic coefficient is in a restricted range. This generalizes previous results in the quadratic case and helps to clarify how to numerically approximate cubic exponential sums and how to obtain upper bounds for them in some cases.
机构:
St. Petersburg Department of the Steklov Mathematical Institute, St. PetersburgSt. Petersburg Department of the Steklov Mathematical Institute, St. Petersburg
机构:
St.Petersburg Department of V. A. Steklov Mathematical Institute of the Russian Academy of Sciences, St.PetersburgSt.Petersburg Department of V. A. Steklov Mathematical Institute of the Russian Academy of Sciences, St.Petersburg
机构:
St. Petersburg Department of the Steklov Mathematical Institute, St. PetersburgSt. Petersburg Department of the Steklov Mathematical Institute, St. Petersburg