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diff --git a/factorizer_qs.py b/factorizer_qs.py | |
index 1368283..e326743 100644 | |
--- a/factorizer_qs.py | |
+++ b/factorizer_qs.py | |
@@ -70,7 +70,7 @@ class QuadraticSieve(Factorizer): | |
x = int(x) | |
candidate = (x+chunk_start)*(x+chunk_start) - N | |
factorization = _is_smooth(candidate) | |
- if factorization is not None: candidates_out[candidate] = factorization | |
+ if factorization is not None: candidates_out[x+chunk_start] = factorization.to_dict() | |
return candidates_out | |
candidates = dict() # dict of {x: x^2 - N} s.t. x^2-N is smooth | |
@@ -86,7 +86,7 @@ class QuadraticSieve(Factorizer): | |
candidates = OrderedDict([(c, candidates[c]) for c in sample(list(candidates), len(primes)+1)]) | |
exponent_vectors = [] | |
for c in candidates: | |
- factorization = candidates[c].to_dict() | |
+ factorization = candidates[c] | |
exponent_vectors.append([factorization[p] % 2 for p in primes ]) | |
# Inspired by https://github.com/mikolajsawicki/quadratic-sieve/blob/main/quadratic_sieve/fast_gauss.py | |
# Also referred to https://www.cs.umd.edu/~gasarch/TOPICS/factoring/fastgauss.pdf | |
@@ -134,11 +134,26 @@ class QuadraticSieve(Factorizer): | |
x = prod(x_s) | |
y = _sqrt_prod(y_s).prod() | |
d = gcd(x-y, N) | |
- if d != 1: | |
- return d | |
+ if d != 1 and d != N: | |
+ return d, N//d | |
else: | |
- print("d == 1, trying again...") | |
+ print("Found a trivial factorization, trying again...") | |
-N = 8754660968220887821 | |
-# N = 1413409093 | |
-x_s, y_s = QuadraticSieve(N).factor() | |
+Ns = [ | |
+ # The original N used in the code | |
+ 8754660968220887821, | |
+ | |
+ # A bunch of extra Ns obtained with random_prime(2^32) * random_prime(2^32) in Sage | |
+ 2288734926177412733, | |
+ 5904209312552100917, | |
+ 504130586996406611, | |
+ 2994875707959333043, | |
+] | |
+ | |
+results = [] | |
+for N in Ns: | |
+ results.append(QuadraticSieve(N).factor()) | |
+ | |
+for N, (x, y) in zip(Ns, results): | |
+ assert x * y == N | |
+ print(f'{N} = {x} * {y}') |
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