9 |
11 |
1 |
S1 |
1 |
S2 |
1 |
S3 |
1 |
Sn |
19 |
21 |
n(2+2n) |
2 |
1 |
Sn |
1 |
n(n+1) |
1 |
n |
1 |
n+1 |
1 |
S1 |
1 |
S2 |
1 |
S3 |
1 |
Sn |
1 |
2 |
1 |
2 |
1 |
3 |
1 |
3 |
1 |
4 |
1 |
n |
1 |
n+1 |
1 |
n+1 |
9 |
11 |
1 |
n+1 |
19 |
21 |
9 |
2 |
19 |
2 |
n(3-bn) |
2 |
S12 |
12 |
S10 |
10 |
A.-2 011 | B.-2 012 | C.-2 010 | D.-2 013 |
b1 |
a1 |
b2 |
a2 |
bn |
an |
1 |
2n |
a-b |
m |
500 |
2n |
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