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Source. Theorem 1.2, PDF p. 3 of arXiv:math/0409279v2, the copy read for this card.

Statement

Let

A={as(ns)}s=1k,B={bt(mt)}t=1ℓA=\{a_s(n_s)\}_{s=1}^k, \qquad B=\{b_t(m_t)\}_{t=1}^{\ell}

be two systems, each with distinct positive integer moduli. Put

N=[n1,…,nk,m1,…,mℓ].N=[n_1,\ldots,n_k,m_1,\ldots,m_{\ell}].

Thus NN is the least common multiple of all moduli in the two systems.

If an integer mm does not divide NN and

wA(x)≡wB(x)(modm)for every x∈Z,w_A(x)\equiv w_B(x)\pmod m \qquad\text{for every }x\in\mathbb Z,

then AA and BB are identical.

Here mm is any integer not dividing NN; positivity is not assumed. The source's Remark 1.3 (PDF p. 3) takes m>Nm>N to recover Znám's 1975 extension of Stein's uniqueness theorem: wA=wBw_A=w_B forces A=BA=B.

Proof pointer. The proof follows Theorem 1.1 in Section 2 and starts on PDF p. 5. It was not reconstructed or independently checked here.