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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 9 |
| 3 | 30 |
| 4 | 90 |
| 5 | 225 |
| 6 | 315 |
| 7 | 630 |
| 8 | 945 |
| 9 | 1575 |
| 10 | 2835 |
| 11 | 4410 |
| 12 | 3465 |
| 13 | 8190 |
| 14 | 6930 |
| 15 | 14175 |
| 16 | 10395 |
| 17 | 27720 |
| 18 | 17325 |
| 19 | 35910 |
| 20 | 31185 |
| 21 | 66150 |
| 22 | 62370 |
| 23 | 99225 |
| 24 | 45045 |
| 25 | 198450 |
| 26 | 90090 |
| 27 | 121275 |
| 28 | 103950 |
| 29 | 207900 |
| 30 | 155925 |
| 31 | 415800 |
| 32 | 135135 |
| 33 | 311850 |
| 34 | 368550 |
| 35 | 353430 |
| 36 | 225225 |
| 37 | 1158300 |
| 38 | 706860 |
[1,9,30,90,225,315,630,945,1575,2835,4410,3465, 8190,6930,14175,10395,27720,17325,35910,31185, 66150,62370,99225,45045,198450,90090,121275, 103950,207900,155925,415800,135135,311850,368550, 353430,225225,1158300,706860] |