We derive total mean curvature integration formulae of a three co-dimensional foliation F n on a screen integrable half-lightlike submanifold, M n+1 in a semi-Riemannian manifold M n+3 . We give generalized differential equations relating to mean curvatures of a totally umbilical half-lightlike submanifold admitting a totally umbilical screen distribution, and show that they are generalizations of those given by [4].2010 Mathematics Subject Classification. Primary 53C25; Secondary 53C40, 53C50. Key words and phrases. Half-lightlike submanifolds; Newton transformation, foliation and mean curvature.
FORTUNÉ MASSAMBA, SAMUEL SSEKAJJAProof. Replacing X with E in the Proposition 5.1 and then using (2.16) and (5.2) we obtain, for all r = 0, 1, · · · , n,from which the result follows by applying (5.4) and (5.5).Corollary 5.3. Under the hypothesis of Theorem 5.2, the induced connection ∇ on M is a metric connection, if and only if, the r-th mean curvature S r with respect to A N are solution of the following equationAlso the following holds. Corollary 5.4. Under the hypothesis of Theorem 5.2, M (c) is a semi-Euclidean space, if and only if, the r-th mean curvature S r with respect to A N are solution of the following equation E(S r+1 ) − τ (E)(r + 1)S r+1 = H 1 (r + 1)S r+1 .