mapping sequence

derive from each of the known functions from the set {seq, dist, pairs, map, -, *}

a. let g be defined by g(n) = <0, 1, 4, ..., n²>
b. let h be defined by h(n) = <2n, 2(n-1), ..., 4, 2, 0>

Having trouble combining these sets with the functions. Do they have to be used in the same order they are given? Any help would be appreciated.