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Defined mathematical notation
Browse 19 linked conservative definitions and 217 theorem bodies without losing their exact first-order expansions.
Browse definitions and theorems →Complete constructive universal representation · Constructive arithmetic
∀ n ∈ ℕ. ∃ a,b,c,d. n = a² + b² + c² + d²
Explore the complete constructive proof that every natural number is a sum of four squares: both Euler quaternion identities, actual bounded prime seeds, all sixteen signed orientations, strict multiplier descent, and explicit prime-factor witnesses.
Current library: Alpha v34, 4,223 checked-use theorems; Stable remains 432. Historical first admissions, original proof editions, and non-admitted aliases are preserved. Exact original first-admission records.
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Browse 19 linked conservative definitions and 217 theorem bodies without losing their exact first-order expansions.
Browse definitions and theorems →Focused route
Follow the selected theorem through its constructive prerequisites, linked definitions, and original proof scripts.
Trace prerequisites →Exact certificate
Inspect 10055 original tactic lines and 717 dependency edges with every definition fully expanded.
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