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| n | a(n) |
|---|---|
| 1 | 25 |
| 2 | 130 |
| 3 | 650 |
| 4 | 2942 |
| 5 | 11445 |
| 6 | 37040 |
| 7 | 101369 |
| 8 | 257799 |
| 9 | 633068 |
| 10 | 1515898 |
| 11 | 3535659 |
| 12 | 7923813 |
| 13 | 16924203 |
| 14 | 34435189 |
| 15 | 67351417 |
| 16 | 127875041 |
| 17 | 237092930 |
| 18 | 430410822 |
| 19 | 764368249 |
| 20 | 1325374142 |
| 21 | 2247755925 |
| 22 | 3735891528 |
| 23 | 6105155090 |
| 24 | 9831802225 |
[25,130,650,2942,11445,37040,101369,257799,633068, 1515898,3535659,7923813,16924203,34435189, 67351417,127875041,237092930,430410822,764368249, 1325374142,2247755925,3735891528,6105155090, 9831802225] |