mathlib

d2b4380c - feat(data/list/basic): list.prod_range_succ, list.sum_range_succ (#1197)

feat(data/list/basic): list.prod_range_succ, list.sum_range_succ (#1197) * feat(data/list/basic): list.prod_range_succ, list.sum_range_succ * changes from review * remove simp * shorten proof