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| n | a(n) |
|---|---|
| 1 | 198 |
| 2 | 747 |
| 3 | 2970 |
| 4 | 11943 |
| 5 | 48024 |
| 6 | 193059 |
| 7 | 776160 |
| 8 | 3120579 |
| 9 | 12546540 |
| 10 | 50444415 |
| 11 | 202816008 |
| 12 | 815438907 |
| 13 | 3278541276 |
| 14 | 13181653431 |
| 15 | 52997956416 |
| 16 | 213082782147 |
| 17 | 856717412004 |
| 18 | 3444505073199 |
| 19 | 13848925017096 |
| 20 | 55680778531323 |
[198,747,2970,11943,48024,193059,776160,3120579, 12546540,50444415,202816008,815438907,3278541276, 13181653431,52997956416,213082782147,856717412004, 3444505073199,13848925017096,55680778531323] |