Question Number 226044 by Jubr last updated on 18/Nov/25
Answered by mr W last updated on 19/Nov/25
$$\mathrm{1}{C}_{\mathrm{50}} ^{\mathrm{1000}} +\mathrm{2}{C}_{\mathrm{49}} ^{\mathrm{999}} +\mathrm{3}{C}_{\mathrm{48}} ^{\mathrm{998}} +…+\mathrm{51}{C}_{\mathrm{0}} ^{\mathrm{950}} \\ $$