1
1 1
1 2 1
1 3 3 1
1 4 6 4 1
1 5 10 10 5 1
1 +1
1 + 2/2+ 1
1 +3/3+3/ 3+ 1
1 + 4/4+ 6 / 4+ 1 머이런식
1 6 15 20 15 6 1