A necessary and sufficient condition that
should be comparable with for all positive values
of the
is that one of ()
and ()
should be majorized by the other. If , then
with equality only when () and () are identical or when all the are equal. See Hardy et al. (1988) for a definition
of notation.
Hardy, G. H.; Littlewood, J. E.; and Pólya, G. "Muirhead's Theorem" and "Proof of Muirhead's Theorem." §2.18
and 2.19 in Inequalities,
2nd ed. Cambridge, England: Cambridge University Press, pp. 44-48, 1988.Muirhead,
R. F. "Some Methods Applicable to Identities and Inequalities of Symmetric
Algebraic Functions of Letters." Proc. Edinburgh Math. Soc.21,
144-157, 1903.