Skolem and Langford sequences and their many generalizations have applications in numerous areas. The ¿h-product is a generalization of the direct product of digraphs. In this paper we use the ¿h-product and super edge-magic digraphs to construct an exponential number of Langford sequences with certain order and defect. We also apply this procedure to extended Skolem sequences.
López, S.C., Muntaner-Batle, F.A. Langford sequences and a product of digraphs. "European journal of combinatorics", 07 Desembre 2015, vol. 53, núm. C, p. 86-95.