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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 11 |
| 3 | 17 |
| 4 | 37 |
| 5 | 82 |
| 6 | 209 |
| 7 | 536 |
| 8 | 1549 |
| 9 | 4513 |
| 10 | 13980 |
| 11 | 44424 |
| 12 | 142457 |
| 13 | 463592 |
| 14 | 1518144 |
| 15 | 4985864 |
| 16 | 16423493 |
| 17 | 54170895 |
| 18 | 178797985 |
| 19 | 590488247 |
| 20 | 1950654770 |
| 21 | 6444889749 |
| 22 | 21296082916 |
| 23 | 70373480203 |
| 24 | 232558689443 |
| 25 | 768538881502 |
| 26 | 2539828012418 |
[3,11,17,37,82,209,536,1549,4513,13980,44424, 142457,463592,1518144,4985864,16423493,54170895, 178797985,590488247,1950654770,6444889749, 21296082916,70373480203,232558689443,768538881502, 2539828012418] |