ちょっと怖い橋もありました。先が見えません。この先へ進んだら殺人鬼の住む小屋がありそうじゃないですか？ Intuitively, The natural range n could be the frequent property of all sets which have n factors. So, It appears natural to outline n being an equivalence class underneath the relation "could be built in one to at least one correspondence". Bea BonmotBea Bonmot 29644 silver badges151... https://jointcarecombo.blogspot.com