Laburnum Laburnum Laburnum, sometimes called golden chain or golden rain, is a genus of two species of small trees in the subfamily Faboideae of the pea family Fabaceae. The species are "Laburnum anagyroides"—common laburnum and "Laburnum alpinum"—alpine laburnum. They are native to the mountains of southern Europe from France to the Balkans. Some botanists include a third species, "Laburnum caramanicum", but this native of southeast Europe and Anatolia is usually treated in a distinct genus "Podocytisus", more closely allied to the "Genisteae" (brooms). The "Laburnum" trees are deciduous. The leaves are trifoliate, somewhat like a clover; the leaflets are typically long
Genus (mathematics) manifold of complex points). For example, the definition of elliptic curve from algebraic geometry is "connected non-singular projective curve of genus 1 with a given rational point on it". By the Riemann-Roch theorem, an irreducible plane curve of degree "d" has geometric genus where "s" is the number of singularities when properly counted. Genus can be also calculated for the graph spanned by the net of chemical interactions in nucleic acids or proteins. In particular, one may study the growth of the genus along the chain. Such a function (called the genus trace) shows the topological complexity and domain structure