n-2 |
n(n+1)(n+2) |
1 |
n(n+1) |
n-2 |
n(n+1)(n+2) |
-1 |
1×2×3 |
5 |
12 |
5 |
24 |
1 |
n(n+1) |
1 |
(n+1)(n+2) |
1 |
n(n+1) |
n-2 |
n(n+1)(n+2) |
2n |
n(n+1)(n+2) |
n+2 |
n(n+1)(n+2) |
n-2 |
n(n+1)(n+2) |
1 |
2 |
1 |
2 |
1 |
2 |
1 |
2 |
1 |
2 |
1 |
2 |
1 |
n(n+1) |
1 |
2 |
1 |
n |
1 |
n+1 |
| ||||
1-
|
1 |
n+1 |
1 |
2 |
1 |
n+1 |
2n-1 |
an |
5-an |
2 |
b1 |
3 |
b2 |
32 |
b3 |
33 |
bn |
3n |
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