On output-based accelerated stabilization of a chain of integrators: Implicit Lyapunov-Krasovskii functional approach⁎This work was partially supported by the Ministry of Science and Higher Education of Russian Federation, passport of goszadanie no. 2019-0898, by Government of Russian Federation (Grant 08-08), by the grant of Russian Federation President (No. MD-1054.2020.8, agreement No. 075-15-2020-184). Issue 2 (2020)