39 lines
932 B
Python
39 lines
932 B
Python
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from lib_prime import primes
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from functools import lru_cache
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@lru_cache
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def next_prime(n):
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if n == 1:
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return 2
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ps = primes(105)
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assert n < ps[-1]
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for i, p in enumerate(ps):
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if p == n and i + 1 < len(ps):
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return ps[i + 1]
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assert False
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def count(current_product, max_product, current_prime, max_prime):
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if current_product > max_product:
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return 0
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r = 1
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if current_prime > 1:
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r += count(current_product * current_prime, max_product, current_prime, max_prime)
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while (current_prime := next_prime(current_prime)) <= max_prime:
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r += count(current_product * current_prime, max_product, current_prime, max_prime)
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return r
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def euler_204():
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assert count(1, 10**8, 1, 5) == 1105
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return count(1, 10**9, 1, 100)
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if __name__ == "__main__":
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solution = euler_204()
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print("e204.py: " + str(solution))
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assert(solution == 2944730)
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