\[ \boxed { {\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}y \left ( x \right ) - \left ( n \left ( n+1 \right ) {\it WeierstrassP} \left ( x,{\it g2},{\it g3} \right ) +B \right ) y \left ( x \right ) =0} \]
Mathematica: cpu = 0.184023 (sec), leaf count = 27 \[ \text {DSolve}\left [y''(x)-y(x) (B+n (n+1) \wp (x;\text {g2},\text {g3}))=0,y(x),x\right ] \]
Maple: cpu = 0.280 (sec), leaf count = 33 \[ \left \{ y \left ( x \right ) ={\it DESol} \left ( \left \{ {\frac { {\rm d}^{2}}{{\rm d}{x}^{2}}}{\it \_Y} \left ( x \right ) + \left ( -n \left ( n+1 \right ) {\it WeierstrassP} \left ( x,{\it g2},{\it g3} \right ) -B \right ) {\it \_Y} \left ( x \right ) \right \} , \left \{ { \it \_Y} \left ( x \right ) \right \} \right ) \right \} \]