Deleting every other number on a circle

The numbers 1,2,…,20001, 2, \dots, 2000 are placed clockwise on a circle. Starting at 11, you delete it, keep the next (22), delete the next (33), keep (44), and so on - alternately deleting and keeping around the circle - until one number remains. Which number survives?

Show hints (2)+
  1. Josephus, step 22, first element deleted. Write n=2m+Ln=2^m+L with 2m≤n2^m\le n.
  2. 2000=1024+9762000=1024+976, survivor =2L=2⋅976=2L=2\cdot976.

Answer

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1952

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