A characterization of weighted approximations by the Post-Widder and the Gamma operators, II

We present a characterization of the approximation errors of the PostWidder and the Gamma operators in Lp(0,∞), 1 ≤ p ≤ ∞, with a weight x0(1 + x)γ∞−γ0 with arbitrary real γ0, γ∞. Two types of characteristics are used – weighted K-functionals of the approximated function itself and the classical fixed step moduli of smoothness taken on simple modifications of it. 2000 Mathematics Subject Classification. Primary 41A25, 41A27; Secondary 41A35, 41A36.