1 |
an |
1 |
an-1 |
1 |
3 |
1 |
S1 |
1 |
S2 |
1 |
Sn |
1 |
3 |
3 |
4 |
1 |
an+1-1 |
1 | ||
1-
|
an |
an-1 |
1 |
an-1 |
an |
an-1 |
1 |
an-1 |
1 |
a1-1 |
1 |
3 |
1 |
3 |
1 |
3 |
n(n+1) |
6 |
1 |
Sn |
6 |
n(n+1) |
1 |
n |
1 |
n+1 |
1 |
S1 |
1 |
S2 |
1 |
Sn |
1 |
2 |
1 |
2 |
1 |
3 |
1 |
n |
1 |
n+1 |
1 |
n+1 |
6n |
n+1 |
1 |
3 |
1 |
3 |
1 |
3 |
1 |
3 |
1 |
3 |
1 |
3 |
1 |
3 |
1 |
3 |
1 |
3 |
1 |
3 |
2 |
3 |
1 |
3 |
1 |
3 |
1 |
3 |
1 |
3 |
1 |
3 |
1 |
2 |
1 |
3 |
1 |
3 |
3 |
4 |
1 |
4 |
1 |
3 |
n |
2 |
1 |
3 |
3 |
4 |
A.12 | B.16 | C.20 | D.24 |
1 |
Tn |
a |
b |
a |
b |
an |
2n |
n-2013 |
n+1 |
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