Invent an equation An imaginary atom is observed to emit electromagnetic radiation at the following wavelengths: 250 nm, 2250 nm, 6250 nm, 12,250 nm, . . . . Invent an empirical equation for calculating these wavelengths; that is, determine $\lambda=f(n),$ where $f$ is an unknown function of an integer

$n,$ which can have the values $1,2,3,4, \ldots$