A nontrivial closed formula for the lower bounds for the constants of the real Hardy-Littlewood inequalities

Abstract: This note has a twofold purpose. To improve the best known lower estimates of the Hardy-Littlewood inequality for $m$-linear forms in $\ell_{p}$ spaces and to provide a closed formula encompassing the cases $p>2m$ and $% p=2m.$ Our approach is quite simpler than the previous and uses the best known constants of the Clarkson's inequalities.