Практичные числа - Numberphile на русском

Оригинал:    • Practical Numbers - Numberphile   NUMBERPHILE Website: http://www.numberphile.com/ Numberphile on Facebook:   / numberphile   Numberphile tweets:   / numberphile   Subscribe: http://bit.ly/Numberphile_Sub Videos by Brady Haran Editing and animation by Pete McPartlan