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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 21 |
| 3 | 132 |
| 4 | 432 |
| 5 | 951 |
| 6 | 1800 |
| 7 | 3069 |
| 8 | 4956 |
| 9 | 7569 |
| 10 | 11040 |
| 11 | 15585 |
| 12 | 21492 |
| 13 | 28971 |
| 14 | 38328 |
| 15 | 49527 |
| 16 | 62922 |
| 17 | 79113 |
| 18 | 98358 |
| 19 | 120939 |
| 20 | 147486 |
| 21 | 177873 |
| 22 | 212358 |
| 23 | 251823 |
| 24 | 296898 |
| 25 | 347709 |
| 26 | 404772 |
| 27 | 468189 |
| 28 | 538680 |
| 29 | 617439 |
| 30 | 704742 |
| 31 | 801039 |
| 32 | 907842 |
| 33 | 1024629 |
| 34 | 1151544 |
| 35 | 1289319 |
| 36 | 1438686 |
[3,21,132,432,951,1800,3069,4956,7569,11040,15585, 21492,28971,38328,49527,62922,79113,98358,120939, 147486,177873,212358,251823,296898,347709,404772, 468189,538680,617439,704742,801039,907842,1024629, 1151544,1289319,1438686] |