Find Sum of Array Product of Magical Sequences

Description

You are given two integers, m and k, and an integer array nums.

A sequence of integers seq is called magical if:

- seq has a size of m.

- 0 <= seq[i] < nums.length

- The binary representation of 2seq[0] + 2seq[1] + ... + 2seq[m - 1] has k set bits.

The array product of this sequence is defined as prod(seq) = (nums[seq[0]] * nums[seq[1]] * ... * nums[seq[m - 1]]).

Return the sum of the array products for all valid magical sequences.

Since the answer may be large, return it modulo 109 + 7.

A set bit refers to a bit in the binary representation of a number that has a value of 1.