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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 5 |
| 4 | 11 |
| 5 | 16 |
| 6 | 36 |
| 7 | 65 |
| 8 | 142 |
| 9 | 285 |
| 10 | 595 |
| 11 | 1210 |
| 12 | 2497 |
| 13 | 5134 |
| 14 | 10726 |
| 15 | 22637 |
| 16 | 48383 |
| 17 | 104066 |
| 18 | 224296 |
| 19 | 481985 |
| 20 | 1030299 |
| 21 | 2188912 |
| 22 | 4626313 |
| 23 | 9743750 |
| 24 | 20492711 |
| 25 | 43114180 |
| 26 | 90843475 |
| 27 | 191776658 |
| 28 | 405528200 |
| 29 | 858384333 |
| 30 | 1817311451 |
| 31 | 3845500427 |
| 32 | 8129033837 |
| 33 | 17162815092 |
[1,1,4,5,11,16,36,65,142,285,595,1210,2497,5134, 10726,22637,48383,104066,224296,481985,1030299, 2188912,4626313,9743750,20492711,43114180, 90843475,191776658,405528200,858384333,1817311451, 3845500427,8129033837,17162815092] |