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    "summary": "Exclude (n,q) = (3,2); q is the fixed-field size, not the matrix-field size.",
    "definition": "The determinant-one isometries of a nondegenerate Hermitian form over F(q²), modulo scalar matrices.",
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            "text": "n = 2: PSU(2,q) ≅ PSL(2,q); these are indexed in the linear family.",
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            "text": "(3,2): PSU(3,2) has order 72 and is not simple.",
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      "title": "Finite simple groups: Lecture 3 — Classical groups",
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      "licenseNote": "Linked for verification. No redistribution licence is asserted; this dataset contains original summaries and selected mathematical facts, not source tables."
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