python - Vectorization of index for flat nested datastructure -

is there function in linear algebra takes vector [a, b, c] , returns vector [bc, c, 1]? or perhaps [abc, bc, c] or [abc, bc, c, 1]?

for homework vectorizing indexing function, take in-product of vector [abc, bc, c, 1] (where letters represent maximum value dimension) vector [0, a, b, c] (where letters represent wanted index each dimension) results in index flat data structure.

i want vectorize getting indexing vector [abc, bc, c] well, can't come matrix or vector creates first vector [a, b, c].

i use python.