let n be non zero Element of NAT ; for A being FinSequence of n -tuples_on BOOLEAN
for C being Subset of (n -BinaryVectSp) st len A = n & A is one-to-one & card (rng A) = n & ( for i, j being Nat st i in Seg n & j in Seg n holds
( ( i = j implies (A . i) . j = TRUE ) & ( i <> j implies (A . i) . j = FALSE ) ) ) & C c= rng A holds
( Lin C is Subspace of n -BinaryVectSp & C is Basis of (Lin C) & dim (Lin C) = card C )
let A be FinSequence of n -tuples_on BOOLEAN; for C being Subset of (n -BinaryVectSp) st len A = n & A is one-to-one & card (rng A) = n & ( for i, j being Nat st i in Seg n & j in Seg n holds
( ( i = j implies (A . i) . j = TRUE ) & ( i <> j implies (A . i) . j = FALSE ) ) ) & C c= rng A holds
( Lin C is Subspace of n -BinaryVectSp & C is Basis of (Lin C) & dim (Lin C) = card C )
let C be Subset of (n -BinaryVectSp); ( len A = n & A is one-to-one & card (rng A) = n & ( for i, j being Nat st i in Seg n & j in Seg n holds
( ( i = j implies (A . i) . j = TRUE ) & ( i <> j implies (A . i) . j = FALSE ) ) ) & C c= rng A implies ( Lin C is Subspace of n -BinaryVectSp & C is Basis of (Lin C) & dim (Lin C) = card C ) )
assume A1:
( len A = n & A is one-to-one & card (rng A) = n & ( for i, j being Nat st i in Seg n & j in Seg n holds
( ( i = j implies (A . i) . j = TRUE ) & ( i <> j implies (A . i) . j = FALSE ) ) ) )
; ( not C c= rng A or ( Lin C is Subspace of n -BinaryVectSp & C is Basis of (Lin C) & dim (Lin C) = card C ) )
assume A2:
C c= rng A
; ( Lin C is Subspace of n -BinaryVectSp & C is Basis of (Lin C) & dim (Lin C) = card C )
reconsider B = rng A as finite Subset of (n -BinaryVectSp) ;
B is linearly-independent
by A1, Th10;
then A3:
C is linearly-independent
by A2, VECTSP_7:1;
for x being object st x in C holds
x in the carrier of (Lin C)
by VECTSP_7:8, STRUCT_0:def 5;
then reconsider C0 = C as Subset of (Lin C) by TARSKI:def 3;
Lin C0 = ModuleStr(# the carrier of (Lin C), the addF of (Lin C), the ZeroF of (Lin C), the lmult of (Lin C) #)
by VECTSP_9:17;
then
C0 is Basis of (Lin C)
by VECTSP_7:def 3, A3, VECTSP_9:12;
hence
( Lin C is Subspace of n -BinaryVectSp & C is Basis of (Lin C) & dim (Lin C) = card C )
by VECTSP_9:def 1; verum