Parity splitting · exact square-and-multiply · canonical modular powers

Constructive binary modular exponentiation

Sixteen independently checked constructive theorems establish exact binary decomposition, square-and-multiply transitions, and existence and uniqueness of the bounded canonical modular power.

16 kernel- and Lean-verified Alpha-closed theorems · 13 conservative definitions · 14 notation dependencies

Alpha v34 checked-use · first admitted v21 · independently kernel and Lean verified; not Stable

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.

29 items
BX0001 binary_modulus_nontrivial_nonzero

Every explicitly guarded modulus m>1 is constructively nonzero.

Alpha v34 checked-use · first admitted v21 · independently kernel and Lean verified; not Stable
BX0002 binary_canonical_residue_exists

Every value has a witnessed canonical residue below every modulus m>1.

Alpha v34 checked-use · first admitted v21 · independently kernel and Lean verified; not Stable
BX0005 binary_exponent_split_exists

Every exponent has an exact half and a witnessed zero-or-one binary digit.

Alpha v34 checked-use · first admitted v21 · independently kernel and Lean verified; not Stable
BX0006 binary_exponent_doubled_power

The relational power at an even exponent is the square of its half power.

Alpha v34 checked-use · first admitted v21 · independently kernel and Lean verified; not Stable
BX0007 binary_exponent_odd_power

The relational power at an odd exponent is its squared half power times the base.

Alpha v34 checked-use · first admitted v21 · independently kernel and Lean verified; not Stable
BX000C binary_modular_step_exists

Every guarded square-and-optional-multiply binary transition has a canonical result.

Alpha v34 checked-use · first admitted v21 · independently kernel and Lean verified; not Stable
BX000D binary_modular_step_functional

A fixed binary digit and state determine exactly one modular transition result.

Alpha v34 checked-use · first admitted v21 · independently kernel and Lean verified; not Stable
PD0002 Lt(a,b)

Witness-defined strict order on natural numbers.

Conservative definition · notation layer 0
ND0021 BinaryModulus(m)

The exact constructive nontrivial-modulus guard 1<m.

Conservative definition · notation layer 1
PD0008 ModEq(m,a,b)

Balanced-natural congruence modulo m.

Conservative definition · notation layer 0
PD0013 BetaAt(b,c,i,x)

x is the bounded beta-decoded value at index i.

Conservative definition · notation layer 0
PD0014 Product(b,c,l,z)

z is the product of a beta-coded prefix of length l.

Conservative definition · notation layer 1
PD0019 Repeat(b,c,a,l)

The decoded prefix repeats a for l positions.

Conservative definition · notation layer 1
PD0020 Pow(a,e,z)

z is the relational e-th power of a.

Conservative definition · notation layer 2
ND0026 BinaryModularStep(m,u,a,b,r)

One exact binary square or square-and-multiply transition with a genuinely canonical reduced output.

Conservative definition · notation layer 2
ND0027 BinaryModularPower(a,e,m,r)

The exact canonical natural residue of the existing beta-coded exponentiation relation Pow(a,e,z).

Conservative definition · notation layer 3

Only proof arrows are theorem dependencies. Definition arrows are hygienic abbreviations of exact first-order formulas and introduce no axiom or kernel symbol.