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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 16 |
| 3 | 64 |
| 4 | 225 |
| 5 | 784 |
| 6 | 2704 |
| 7 | 9409 |
| 8 | 32761 |
| 9 | 114244 |
| 10 | 398161 |
| 11 | 1387684 |
| 12 | 4835601 |
| 13 | 16851025 |
| 14 | 58721569 |
| 15 | 204633025 |
| 16 | 713103616 |
| 17 | 2485022500 |
| 18 | 8659791364 |
| 19 | 30177596089 |
| 20 | 105162706944 |
| 21 | 366470415424 |
| 22 | 1277074025929 |
| 23 | 4450340433889 |
| 24 | 15508521343396 |
[4,16,64,225,784,2704,9409,32761,114244,398161, 1387684,4835601,16851025,58721569,204633025, 713103616,2485022500,8659791364,30177596089, 105162706944,366470415424,1277074025929, 4450340433889,15508521343396] |