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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 81 |
| 3 | 169 |
| 4 | 441 |
| 5 | 1225 |
| 6 | 2809 |
| 7 | 6241 |
| 8 | 14161 |
| 9 | 31329 |
| 10 | 68121 |
| 11 | 148225 |
| 12 | 321489 |
| 13 | 693889 |
| 14 | 1495729 |
| 15 | 3222025 |
| 16 | 6932689 |
| 17 | 14907321 |
| 18 | 32046921 |
| 19 | 68873401 |
| 20 | 147987225 |
| 21 | 317944561 |
| 22 | 683038225 |
| 23 | 1467273025 |
| 24 | 3151811881 |
| 25 | 6770162961 |
| 26 | 14542189281 |
| 27 | 31235967169 |
[9,81,169,441,1225,2809,6241,14161,31329,68121, 148225,321489,693889,1495729,3222025,6932689, 14907321,32046921,68873401,147987225,317944561, 683038225,1467273025,3151811881,6770162961, 14542189281,31235967169] |