… Elliptic and hyperbolic cylindrical curves satisfying Tzitzeica condition are obtained via the
solution of the forced harmonic equation. … In this paper we are interested in Tzitzeica
cylindrical curves, more precisely we ask in what conditions a cylindrical curve is a Tzitzeica
one, namely the function … Therefore the final answer of main problem is given via a second
order ODE which in the elliptic case is exactly the equation of a forced harmonic oscillator! In
both cases, elliptic and hyperbolic, the solution depends of four real constants: one defining the …