for X being RealNormSpace
for f being sequence of (DualSp X)
for x being sequence of X st ||.f.|| is bounded holds
ex F being sequence of (Funcs (NAT, the carrier of (DualSp X))) st
( F . 0 is subsequence of f & (F . 0) # (x . 0) is convergent & ( for k being Nat holds F . (k + 1) is subsequence of F . k ) & ( for k being Nat holds (F . (k + 1)) # (x . (k + 1)) is convergent ) )