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| n | a(n) |
|---|---|
| 0 | 25 |
| 1 | 51 |
| 2 | 178 |
| 3 | 407 |
| 4 | 992 |
| 5 | 1399 |
| 6 | 2391 |
| 7 | 10963 |
| 8 | 276466 |
| 9 | 1116827 |
| 10 | 1393293 |
| 11 | 2510120 |
| 12 | 6413533 |
| 13 | 15337186 |
| 14 | 52425091 |
| 15 | 120187368 |
| 16 | 6061793491 |
| 17 | 12243774350 |
| 18 | 42793116541 |
| 19 | 97830007432 |
| 20 | 238453131405 |
| 21 | 336283138837 |
[25,51,178,407,992,1399,2391,10963,276466,1116827, 1393293,2510120,6413533,15337186,52425091, 120187368,6061793491,12243774350,42793116541, 97830007432,238453131405,336283138837] |