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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 27 |
| 3 | 264 |
| 4 | 2703 |
| 5 | 28443 |
| 6 | 304740 |
| 7 | 3306852 |
| 8 | 36225519 |
| 9 | 399755001 |
| 10 | 4437142467 |
| 11 | 49485052224 |
| 12 | 554059164036 |
| 13 | 6224177431332 |
| 14 | 70120015345512 |
| 15 | 791898021185484 |
| 16 | 8962485528377583 |
| 17 | 101626868754849381 |
| 18 | 1154295872365035537 |
| 19 | 13130360954151723480 |
| 20 | 149562006735075309783 |
[1,3,27,264,2703,28443,304740,3306852,36225519, 399755001,4437142467,49485052224,554059164036, 6224177431332,70120015345512,791898021185484, 8962485528377583,101626868754849381, 1154295872365035537,13130360954151723480, 149562006735075309783] |