Published online by Cambridge University Press: 07 June 2012
We prove that for an operator T on ℓ∞(H1 ()), respectively ℓ∞(L1 (
)), the identity factors through T or Id - T. Hence ℓ∞(H1 (
)) and ℓ∞(L1 (
)) are primary spaces. We re-prove analogous results of H.M. Wark for the spaces ℓ∞(Hp(
)), 1 < p < ∞. In the present paper direct combinatorics of colored dyadic intervals replaces the dependence on Szemerédi's theorem in [11].