\[
\boxed{
{\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}y \left( x \right) - \left( 1/30\,{\frac {{\rm d}^{4}}{{\rm d}{x}^{4}}}p \left( x \right) +7/3\,{\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}p \left( x \right) +ap \left( x \right) +b \right) y \left( x \right) =0}
\]