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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 9 |
| 3 | 45 |
| 4 | 139 |
| 5 | 333 |
| 6 | 684 |
| 7 | 1258 |
| 8 | 2133 |
| 9 | 3402 |
| 10 | 5167 |
| 11 | 7542 |
| 12 | 10656 |
| 13 | 14647 |
| 14 | 19665 |
| 15 | 25875 |
| 16 | 33451 |
| 17 | 42579 |
| 18 | 53460 |
| 19 | 66304 |
| 20 | 81333 |
| 21 | 98784 |
| 22 | 118903 |
| 23 | 141948 |
| 24 | 168192 |
| 25 | 197917 |
| 26 | 231417 |
| 27 | 269001 |
| 28 | 310987 |
| 29 | 357705 |
| 30 | 409500 |
| 31 | 466726 |
| 32 | 529749 |
| 33 | 598950 |
| 34 | 674719 |
[0,1,9,45,139,333,684,1258,2133,3402,5167,7542, 10656,14647,19665,25875,33451,42579,53460,66304, 81333,98784,118903,141948,168192,197917,231417, 269001,310987,357705,409500,466726,529749,598950, 674719] |