Kata

A natural number is called k-prime if it has exactly k prime factors, counted with multiplicity. A natural number is thus prime if and only if it is 1-prime.

Examples:
k = 2 -> 4, 6, 9, 10, 14, 15, 21, 22, …
k = 3 -> 8, 12, 18, 20, 27, 28, 30, …
k = 5 -> 32, 48, 72, 80, 108, 112, …

Task:

Given an integer k and a list arr of positive integers the function consec_kprimes (or its variants in other languages) returns how many times in the sequence arr numbers come up twice in a row with exactly k prime factors?

Examples:

arr = [10005, 10030, 10026, 10008, 10016, 10028, 10004]
consec_kprimes(4, arr) => 3 because 10005 and 10030 are consecutive 4-primes, 10030 and 10026 too as well as 10028 and 10004 but 10008 and 10016 are 6-primes.

consec_kprimes(4, [10175, 10185, 10180, 10197]) => 3 because 10175-10185 and 10185- 10180 and 10180-10197 are all consecutive 4-primes.

Note:

It could be interesting to begin with: https://www.codewars.com/kata/k-primes