三角形=乘法表的向上倾斜对角线：
.
1,..2,..三，。。4,..5,..6,..7,...
1,..2,..三，。。4,..5,..6,..7,...
2,..4,..6,..8,.10,.12,.14,...
2,..4,..6,..8,.10,.12,.14,...
…三角形的前几行=
.
1;
1, 2;
2, 2, 3;
2, 4, 3, 4;
4, 4, 6, 4, 5;
4, 8, 6, 8, 5, 6;
7, 8, 12, 8, 10, 6, 7;
8, 14, 12, 16, 10, 12, 7, 8;
12, 16, 21, 16, 20, 12, 14, 8, 9;
14, 24, 24, 28, 20, 24, 14, 10, 9, 10;
21, 28, 36, 32, 35, 24, 28, 16, 18, 10, 11;
24, 42, 42, 48, 40, 42, 28, 32, 18, 20, 11, 12;
34, 48, 63, 56, 60, 48, 49, 32, 36, 20, 22, 12, 13;
41, 68, 72, 84, 70, 72, 56, 56, 36, 40, 22, 24, 13, 14;
...
