MathDB
Writing numbers on a blackboard

Source: 2024 CTST P11

March 12, 2024
combinatorics

Problem Statement

There is number 11 on the blackboard initially. The first step is to erase 11 and write two nonnegative reals whose sum is 11. Call the smaller number of the two L2L_2. For integer k2k \ge 2, the k{k} the step is to erase a number on the blackboard arbitrarily and write two nonnegative reals whose sum is the number erased just now. Call the smallest number of the k+1k+1 on the blackboard Lk+1L_{k+1}. Find the maximum of L2+L3++L2024L_2+L_3+\cdots+L_{2024}.