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Problem 50811. Compute the nth term from the Sieve of Flavius Josephus

To apply the Sieve of Eratosthenes, start with the natural numbers (skipping 1), keep the first number (i.e., 2), and delete all multiples (4, 6, 8, 10, etc.). Then repeat: keep the first remaining number (3) and delete all multiples (9, 15, 21, etc.). The remaining numbers are the primes.
To apply the Sieve of Flavius Josephus, start with the natural numbers. On the kth step, remove every (k+1)st term remaining after the (k-1)st step. So, on the first step, remove every second number (2, 4, 6, 8, etc.) to leave 1, 3, 5, 7, 9, 11, 13, 15, 17…On the second step, remove every third number (5, 11, 17, etc.) to leave 1, 3, 7, 9, 13, 15, 19,…
Write a function to compute the nth term in the sequence remaining after the Sieve of Flavius Josephus is applied.
Solve

Solution Stats

60.0% Correct | 40.0% Incorrect
Last Solution submitted on Sep 12, 2023

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