Problem 52669. Count the primes in Collatz sequences

Several Cody problems (21, 69, 42937, 44448, 44784, 52422) involve Collatz sequences. These start with a seed n. If n is odd, the next element is 3n+1, and if n is even, the next element is n/2. For example, if the seed is 3, then the sequence is 3, 10, 5, 16, 8, 4, 2, 1. The Collatz conjecture is that all of these sequences terminate at the value 1; that is, all seeds lead to terminating sequences.
This problem deals with the number of primes in the sequence. With a seed of 3, the number of primes is 3 (2, 3, 5).
Write a function to determine the numbers of primes in the sequences with seeds of 1 to the input number. See the test suite for banned terms and commands.
Solve

Solution Stats

78.26% Correct | 21.74% Incorrect
Last Solution submitted on Aug 01, 2025

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