Естаева, Г., and Т. . Сагындыков. “APPLICATION OF THE MATHEMATICAL INDUCTION METHOD IN NON-STANDARD PROBLEMS”. Bulletin of Abai KazNPU. Series of Physical and Mathematical Sciences, vol. 69, no. 1, June 2021, pp. 71-78, https://bulletin-phmath.kaznpu.kz/index.php/ped/article/view/169.