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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 31 |
| 3 | 212 |
| 4 | 812 |
| 5 | 2313 |
| 6 | 5463 |
| 7 | 11344 |
| 8 | 21424 |
| 9 | 37625 |
| 10 | 62375 |
| 11 | 98676 |
| 12 | 150156 |
| 13 | 221137 |
| 14 | 316687 |
| 15 | 442688 |
| 16 | 605888 |
| 17 | 813969 |
| 18 | 1075599 |
| 19 | 1400500 |
| 20 | 1799500 |
| 21 | 2284601 |
| 22 | 2869031 |
| 23 | 3567312 |
| 24 | 4395312 |
| 25 | 5370313 |
| 26 | 6511063 |
| 27 | 7837844 |
| 28 | 9372524 |
| 29 | 11138625 |
| 30 | 13161375 |
[0,1,31,212,812,2313,5463,11344,21424,37625,62375, 98676,150156,221137,316687,442688,605888,813969, 1075599,1400500,1799500,2284601,2869031,3567312, 4395312,5370313,6511063,7837844,9372524,11138625, 13161375] |