1 |
u |
1 |
u |
1 |
u |
1 |
u |
1 |
u |
2 |
10 |
3 |
10 |
4 |
10 |
5 |
10 |
6 |
10 |
7 |
10 |
8 |
10 |
9 |
10 |
4 |
10 |
2 |
5 |
2 |
10 |
3 |
10 |
4 |
10 |
5 |
10 |
6 |
10 |
7 |
10 |
8 |
10 |
9 |
10 |
1 |
2 |
1 |
2 |
4 |
3 |
4 |
3 |
3 |
4 |
3 |
4 |
1 |
2 |
1 |
3 |
1 |
4 |
1 |
5 |
1 |
10 |
1 |
10 |
1 |
2012 |
1 |
a-1 |
加数的个数n | S |
1 | 2=1×2 |
2 | 2+4=6=2×3 |
3 | 2+4+6=12=3×4 |
4 | 2+4+6+8=20=4×5 |
5 | 2+4+6+8+10=30=5×6 |
n(n-1) |
2 |
n(n-1) |
2 |