Mehta, RanjanaRanjanaMehtaSaha, JoydipJoydipSahaSengupta, IndranathIndranathSengupta2025-08-282025-08-282025-06-0110.48550/arXiv.2506.09400https://d8.irins.org/handle/IITG2025/20167We study the tangent cone at the origin and the Hilbert series for a family of numerical semigroups generated by concatenation of arithmetic sequences. We prove that all the concatenation classes have Cohen-Macaulay tangent cones except the symmetric class, however, the symmetric class does satisfy Rossi's conjecture.en-USe-Printe-Print123456789/555