12=2^2*3可以看作是p-adic估值的序列(2,1,0,…),20=2^2*5可以看作是(2,0,1,O,…);(2,0,1,0,…)按字典顺序排在(2,1,O,…)之前,因此从这个角度来看,20“<”12。
三角形开始于:
1,
1, 2,
1, 3, 2,
1, 3, 2, 4,
1, 5, 3, 2, 4,
1, 5, 3, 2, 6, 4,
1, 7, 5, 3, 2, 6, 4,
1, 7, 5, 3, 2, 6, 4, 8,
1, 7, 5, 3, 9, 2, 6, 4, 8,
1, 7, 5, 3, 9, 2, 10, 6, 4, 8,
1, 11, 7, 5, 3, 9, 2, 10, 6, 4, 8,
1, 11, 7, 5, 3, 9, 2, 10, 6, 4, 12, 8,
1, 13, 11, 7, 5, 3, 9, 2, 10, 6, 4, 12, 8,
1, 13, 11, 7, 5, 3, 9, 2, 14, 10, 6, 4, 12, 8,
1, 13, 11, 7, 5, 3, 15, 9, 2, 14, 10, 6, 4, 12, 8,
1, 13, 11, 7, 5, 3, 15, 9, 2, 14, 10, 6, 4, 12, 8, 16,
1, 17, 13, 11, 7, 5, 3, 15, 9, 2, 14, 10, 6, 4, 12, 8, 16,
1, 17, 13, 11, 7, 5, 3, 15, 9, 2, 14, 10, 6, 18, 4, 12, 8, 16,
1, 19, 17, 13, 11, 7, 5, 3, 15, 9, 2, 14, 10, 6, 18, 4, 12, 8, 16,
1, 19, 17, 13, 11, 7, 5, 3, 15, 9, 2, 14, 10, 6, 18, 4, 20, 12, 8, 16,