k and d-1k and d-2k and d-3k and d-4k and d-5k and d-6k and d-7k and d-8k and d-9k and d-10k and d-11k and d-12k and d-13k and d-14k and d-15k and d-16k and d-17k and d-18k and d-19k and d-20