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| n | a(n) |
|---|---|
| 1 | 10 |
| 2 | 100 |
| 3 | 270 |
| 4 | 1035 |
| 5 | 3315 |
| 6 | 8280 |
| 7 | 23400 |
| 8 | 56814 |
| 9 | 136114 |
| 10 | 322834 |
| 11 | 725005 |
| 12 | 1627260 |
| 13 | 3560880 |
| 14 | 7664285 |
| 15 | 16349062 |
| 16 | 34340640 |
| 17 | 71524992 |
| 18 | 147574233 |
| 19 | 301825437 |
| 20 | 613141606 |
| 21 | 1236720905 |
| 22 | 2479598284 |
| 23 | 4944012260 |
| 24 | 9806225404 |
| 25 | 19359765906 |
[10,100,270,1035,3315,8280,23400,56814,136114, 322834,725005,1627260,3560880,7664285,16349062, 34340640,71524992,147574233,301825437,613141606, 1236720905,2479598284,4944012260,9806225404, 19359765906] |