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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 28 |
| 2 | 198 |
| 3 | 1363 |
| 4 | 9348 |
| 5 | 64078 |
| 6 | 439203 |
| 7 | 3010348 |
| 8 | 20633238 |
| 9 | 141422323 |
| 10 | 969323028 |
| 11 | 6643838878 |
| 12 | 45537549123 |
| 13 | 312119004988 |
| 14 | 2139295485798 |
| 15 | 14662949395603 |
| 16 | 100501350283428 |
| 17 | 688846502588398 |
| 18 | 4721424167835363 |
| 19 | 32361122672259148 |
[3,28,198,1363,9348,64078,439203,3010348,20633238, 141422323,969323028,6643838878,45537549123, 312119004988,2139295485798,14662949395603, 100501350283428,688846502588398,4721424167835363, 32361122672259148] |