Symplectic meanders
  Analogous to the sl(n) case, we address the computation of the index of seaweed subalgebras of sp(2n) by introducing graphical representations called symplectic meanders. Formulas for the algebra's index may be computed by counting the connected components of its associated meander. In certain cases, formulas for the index can be given in terms of elementary functions. 
Vincent E. Coll, Jr., Matthew Hyatt, Colton Magnant
math.RA math.RT