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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 9 |
| 3 | 31 |
| 4 | 100 |
| 5 | 317 |
| 6 | 1000 |
| 7 | 3150 |
| 8 | 9918 |
| 9 | 31223 |
| 10 | 98289 |
| 11 | 309406 |
| 12 | 973981 |
| 13 | 3065996 |
| 14 | 9651448 |
| 15 | 30381786 |
| 16 | 95638797 |
| 17 | 301061279 |
| 18 | 947710512 |
| 19 | 2983297009 |
| 20 | 9391117780 |
| 21 | 29562290606 |
| 22 | 93059106094 |
| 23 | 292940670339 |
| 24 | 922147653681 |
| 25 | 2902827709802 |
| 26 | 9137808548505 |
| 27 | 28764898718296 |
| 28 | 90548996937472 |
[1,9,31,100,317,1000,3150,9918,31223,98289,309406, 973981,3065996,9651448,30381786,95638797, 301061279,947710512,2983297009,9391117780, 29562290606,93059106094,292940670339,922147653681, 2902827709802,9137808548505,28764898718296, 90548996937472] |