Hierarchical curl-conforming Nedelec elements for triangular-prism cells

New curl-conforming hierarchical vector basis functions are developed for triangular-prism cells. These bases are constructed by taking the product of base vectors with scalar orthogonal polynomials and are shown to maintain linear independence as their polynomial order is increased. The procedure for constructing these basis functions is described and specific functions are tabulated for orders up to 6.5. These bases are compatible with recently-proposed hierarchical bases for tetrahedral and hexahedral cells and will maintain tangential continuity with those bases if used in a mesh containing multiple cell shapes.