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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 6 |
| 4 | 11 |
| 5 | 66 |
| 6 | 171 |
| 7 | 363 |
| 8 | 7227 |
| 9 | 66566 |
| 10 | 154451 |
| 11 | 685586 |
| 12 | 3279723 |
| 13 | 6441446 |
| 14 | 8503058 |
| 15 | 8916198 |
| 16 | 13155131 |
| 17 | 20611602 |
| 18 | 110313011 |
| 19 | 19833933891 |
| 20 | 72288388227 |
| 21 | 89064046098 |
| 22 | 179298892971 |
| 23 | 814860068418 |
| 24 | 1103556553011 |
| 25 | 3406132316043 |
| 26 | 6205240425026 |
| 27 | 30403655630403 |
| 28 | 206380232083602 |
| 29 | 666150525051666 |
[2,3,6,11,66,171,363,7227,66566,154451,685586, 3279723,6441446,8503058,8916198,13155131,20611602, 110313011,19833933891,72288388227,89064046098, 179298892971,814860068418,1103556553011, 3406132316043,6205240425026,30403655630403, 206380232083602,666150525051666] |