https://qiita.com/kiyamada/items/087de76a9610673c7818#comment-8062e6da32e717c1e04b

betweennumbers.py

def solve(cards, numbers):
    if not numbers:
        yield cards[:]
        return
    left = cards.index(0)
    for number in numbers:
        if (right := left + number + 1) < len(cards) and cards[right] == 0:
            cards[left] = cards[right] = number
            yield from solve(cards, numbers - {number})
            cards[left] = cards[right] = 0

uniq = []
for cards in solve([0] * 14, set(range(1, 8))):
    if cards[::-1] not in uniq:
        uniq.append(cards)
for i, cards in enumerate(uniq, 1):
    print(f'No.{i:2}', cards)