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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 4 |
| 4 | 9 |
| 5 | 144 |
| 6 | 441 |
| 7 | 1444 |
| 8 | 29929 |
| 9 | 55225 |
| 10 | 166464 |
| 11 | 255025 |
| 12 | 299209 |
| 13 | 633616 |
| 14 | 646416 |
| 15 | 767376 |
| 16 | 4999696 |
| 17 | 9696996 |
| 18 | 34433424 |
| 19 | 228281881 |
| 20 | 414041104 |
| 21 | 414488881 |
| 22 | 424442404 |
| 23 | 536663556 |
| 24 | 969699600 |
| 25 | 1649496996 |
| 26 | 1929229929 |
| 27 | 2636206336 |
| 28 | 2666999449 |
| 29 | 2929299129 |
| 30 | 2996029696 |
| 31 | 4664343616 |
[0,1,4,9,144,441,1444,29929,55225,166464,255025, 299209,633616,646416,767376,4999696,9696996, 34433424,228281881,414041104,414488881,424442404, 536663556,969699600,1649496996,1929229929, 2636206336,2666999449,2929299129,2996029696, 4664343616] |