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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 11 |
| 4 | 33 |
| 5 | 94 |
| 6 | 279 |
| 7 | 803 |
| 8 | 2348 |
| 9 | 6823 |
| 10 | 19879 |
| 11 | 57834 |
| 12 | 168405 |
| 13 | 490125 |
| 14 | 1426824 |
| 15 | 4153197 |
| 16 | 12089787 |
| 17 | 35191868 |
| 18 | 102440785 |
| 19 | 298194567 |
| 20 | 868017488 |
| 21 | 2526715121 |
| 22 | 7355031727 |
| 23 | 21409798576 |
| 24 | 62321907805 |
| 25 | 181413177769 |
| 26 | 528076639862 |
| 27 | 1537181201003 |
| 28 | 4474589318797 |
| 29 | 13025106833162 |
| 30 | 37914855831345 |
[1,1,4,11,33,94,279,803,2348,6823,19879,57834, 168405,490125,1426824,4153197,12089787,35191868, 102440785,298194567,868017488,2526715121, 7355031727,21409798576,62321907805,181413177769, 528076639862,1537181201003,4474589318797, 13025106833162,37914855831345] |