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| n | a(n) |
|---|---|
| 1 | 2554 |
| 2 | 13349 |
| 3 | 66542 |
| 4 | 262251 |
| 5 | 844499 |
| 6 | 2396710 |
| 7 | 6268245 |
| 8 | 15240141 |
| 9 | 34366037 |
| 10 | 73532563 |
| 11 | 151376143 |
| 12 | 300641702 |
| 13 | 577321492 |
| 14 | 1080395302 |
| 15 | 1979809481 |
| 16 | 3555813611 |
| 17 | 6272004915 |
| 18 | 10905756945 |
| 19 | 18725699038 |
| 20 | 31765068089 |
| 21 | 53317281722 |
| 22 | 88726986314 |
[2554,13349,66542,262251,844499,2396710,6268245, 15240141,34366037,73532563,151376143,300641702, 577321492,1080395302,1979809481,3555813611, 6272004915,10905756945,18725699038,31765068089, 53317281722,88726986314] |