pub(crate) fn degrees(
l: i32,
m: i32,
lambda: i32,
mu: i32,
cross: bool,
) -> impl ExactSizeIterator<Item = i32>Expand description
Degrees p that tl_vsw_term admits for source (l, m) and destination
(lambda, mu), descending in steps of two. formal/Formal/SelectionRules.lean proves
this range.