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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 225 |
| 3 | 4033 |
| 4 | 59127 |
| 5 | 872437 |
| 6 | 12867295 |
| 7 | 191707377 |
| 8 | 2851740545 |
| 9 | 42351530487 |
| 10 | 628917557052 |
| 11 | 9343657589877 |
| 12 | 138832484811480 |
| 13 | 2062679454951201 |
| 14 | 30644671161036036 |
| 15 | 455284849342096283 |
| 16 | 6764205083943142280 |
[21,225,4033,59127,872437,12867295,191707377, 2851740545,42351530487,628917557052,9343657589877, 138832484811480,2062679454951201, 30644671161036036,455284849342096283, 6764205083943142280] |