Unique binary digits · strictly increasing powers · full unique bit length

Constructive binary length and powers of two

Twenty-one independently checked constructive theorems prove unique binary digit decomposition, strict power-of-two growth, and existence and uniqueness of the exact canonical bit length for every natural number.

21 kernel- and Lean-verified Alpha-closed theorems · 10 conservative definitions · 11 notation dependencies

Alpha v34 checked-use · first admitted v22 · 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.

31 items
BL0001 binary_length_digit_bounded

Every witnessed binary digit is strictly below two.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
BL0002 binary_length_digit_split_exists

Every natural number has an exact binary quotient and zero-or-one digit.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
BL0005 binary_power_two_exists

Every natural exponent has a witnessed beta-coded power of two.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
BL0006 binary_power_two_functional

The relational power of two is functional at every exponent.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
BL0007 binary_power_two_zero_value

The beta-coded zeroth power of two is exactly one.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
BL0008 binary_power_two_nonzero

Every beta-coded power of two is constructively nonzero.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
BL0009 binary_power_two_successor_double

A successor power of two is exactly the sum of two predecessor powers.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
BL000B binary_power_two_exponent_monotone

The relational powers of two preserve non-strict exponent ordering.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
BL000C binary_power_two_exponent_strict

Strictly ordered exponents have strictly ordered powers of two.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
BL000D binary_length_zero

The blueprint convention gives zero exactly one displayed binary digit.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
BL000E binary_length_one

The positive integer one has exactly one binary digit.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
BL000F binary_length_zero_input_value

Any binary-length witness for zero is necessarily one.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
BL0010 binary_length_successor_step

A binary-length witness for n constructively produces one for S n.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
BL0011 binary_length_exists

Every natural number has a constructively witnessed canonical bit length.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
BL0012 binary_length_zero_input_general

Any canonical bit-length witness at an input equal to zero is one.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
BL0013 binary_length_functional

Two complete constructive binary-length witnesses for one input agree.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
BL0014 binary_length_exists_unique

Every natural has exactly one canonical blueprint-compatible bit length.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
BL0015 binary_length_power_exact

The exact beta-coded power 2^e has canonical binary length e+1.

Alpha v34 checked-use · first admitted v22 · independently kernel and Lean verified; not Stable
PD0002 Lt(a,b)

Witness-defined strict order on natural numbers.

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
ND0028 PowTwo(e,p)

The exact existing constructive exponentiation relation Pow(2,e,p).

Conservative definition · notation layer 3
ND0029 BinaryDigit(n,h,b)

An exact binary digit split n=2h+b, with b explicitly zero or one.

Conservative definition · notation layer 1
PD0001 Le(a,b)

Witness-defined non-strict order on natural numbers.

Conservative definition · notation layer 0
ND0030 BitLen(n,ell)

The unique binary length, with BitLen(0,1) and positive bounds 2^(ell-1)≤n<2^ell.

Conservative definition · notation layer 4

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