Matrix transforms into the speed-Maddox spaces over ultrametric fields

Let K be a complete, non-trivially valued, ultrametric (or non-archimedean) field. Entries of sequences, infinite series and infinite matrices are in K. In this paper are defined the notions of speed-Maddox spaces over K, where the speed is defined by a sequence μ = {μn} in K with the property 0 < |μn| ↗ ∞, n → ∞. Let λ be another speed in K. The necessary and sufficient conditions for a matrix A would transform all sequences that are λ-convergent to zero over K into the speed-Maddox spaces over K, where the speed is defined by μ.