%0 Journal Article
%T Sharpness of Muqattash-Yahdi problem
%A Chen
%A Chao-Ping
%A Mortici
%A Cristinel
%J Computational & Applied Mathematics
%D 2012
%I Scientific Electronic Library Online
%R 10.1590/S1807-03022012000100005
%X let ¦× denote the psi (or digamma) function. we determine the values of theparameters p, q and r such that ¦×(n) ¡Ö ln(n + p) - is the best approximations. also, we present closer bounds for psi function, which sharpens some known results due to muqattash and yahdi, qi and guo, and mortici. mathematical subject classification: 33b15, 26d15.
%K psi function
%K polygamma functions
%K rate of convergence
%K approximations.
%U http://www.scielo.br/scielo.php?script=sci_abstract&pid=S1807-03022012000100005&lng=en&nrm=iso&tlng=en