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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 38 |
| 4 | 172 |
| 5 | 794 |
| 6 | 3738 |
| 7 | 17830 |
| 8 | 85774 |
| 9 | 415198 |
| 10 | 2020718 |
| 11 | 9873217 |
| 12 | 48400818 |
| 13 | 237896624 |
| 14 | 1171802761 |
| 15 | 5782520122 |
| 16 | 28578832172 |
| 17 | 141428488154 |
| 18 | 700672333743 |
| 19 | 3474632854006 |
| 20 | 17245086671574 |
| 21 | 85652143372137 |
| 22 | 425684645188303 |
| 23 | 2116810581506954 |
| 24 | 10531537984565389 |
| 25 | 52419539328903339 |
| 26 | 261014994119075193 |
[1,2,9,38,172,794,3738,17830,85774,415198,2020718, 9873217,48400818,237896624,1171802761,5782520122, 28578832172,141428488154,700672333743, 3474632854006,17245086671574,85652143372137, 425684645188303,2116810581506954, 10531537984565389,52419539328903339, 261014994119075193] |