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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 9 |
| 2 | 44 |
| 3 | 156 |
| 4 | 449 |
| 5 | 1113 |
| 6 | 2463 |
| 7 | 4983 |
| 8 | 9372 |
| 9 | 16588 |
| 10 | 27886 |
| 11 | 44846 |
| 12 | 69387 |
| 13 | 103763 |
| 14 | 150538 |
| 15 | 212538 |
| 16 | 292779 |
| 17 | 394371 |
| 18 | 520399 |
| 19 | 673783 |
| 20 | 857121 |
| 21 | 1072521 |
| 22 | 1321430 |
| 23 | 1604470 |
| 24 | 1921291 |
| 25 | 2270451 |
| 26 | 2649332 |
| 27 | 3054100 |
| 28 | 3479715 |
| 29 | 3919995 |
| 30 | 4367735 |
[1,9,44,156,449,1113,2463,4983,9372,16588,27886, 44846,69387,103763,150538,212538,292779,394371, 520399,673783,857121,1072521,1321430,1604470, 1921291,2270451,2649332,3054100,3479715,3919995, 4367735] |