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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 16 |
| 3 | 36 |
| 4 | 81 |
| 5 | 196 |
| 6 | 484 |
| 7 | 1225 |
| 8 | 3136 |
| 9 | 8100 |
| 10 | 21025 |
| 11 | 54756 |
| 12 | 142884 |
| 13 | 373321 |
| 14 | 976144 |
| 15 | 2553604 |
| 16 | 6682225 |
| 17 | 17489124 |
| 18 | 45778756 |
| 19 | 119836809 |
| 20 | 313714944 |
| 21 | 821280964 |
| 22 | 2150084161 |
| 23 | 5628900676 |
| 24 | 14736503236 |
| 25 | 38580423561 |
| 26 | 101004467344 |
| 27 | 264432492900 |
[4,16,36,81,196,484,1225,3136,8100,21025,54756, 142884,373321,976144,2553604,6682225,17489124, 45778756,119836809,313714944,821280964,2150084161, 5628900676,14736503236,38580423561,101004467344, 264432492900] |