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| n | a(n) |
|---|---|
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 11 |
| 8 | 37 |
| 9 | 125 |
| 10 | 421 |
| 11 | 1405 |
| 12 | 4637 |
| 13 | 15125 |
| 14 | 48777 |
| 15 | 155665 |
| 16 | 492157 |
| 17 | 1543269 |
| 18 | 4804663 |
| 19 | 14865495 |
| 20 | 45745953 |
| 21 | 140118817 |
| 22 | 427445507 |
| 23 | 1299383403 |
| 24 | 3937901525 |
| 25 | 11902380845 |
| 26 | 35891429675 |
| 27 | 108009437323 |
| 28 | 324455779889 |
| 29 | 973119941425 |
[1,1,3,11,37,125,421,1405,4637,15125,48777,155665, 492157,1543269,4804663,14865495,45745953, 140118817,427445507,1299383403,3937901525, 11902380845,35891429675,108009437323,324455779889, 973119941425] |