A Novel Explicit Two-Derivative Runge–Kutta–Nyström Method with Energy Conservation for the Integration of Second-Order Periodic ODEs. Eur. J. Pure Appl. Math. [Internet]. 2025 Nov. 5 [cited 2025 Dec. 5];18(4):6042. Available from: https://www.ejpam.com/index.php/ejpam/article/view/6042