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 st term remaining after the 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.
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Nikolaos Nikolaou
on 17 Mar 2024
Making me thing that i can get away with brute force was vicious at the very least :D
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