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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 4 |
| 3 | 9 |
| 4 | 121 |
| 5 | 252 |
| 6 | 484 |
| 7 | 10201 |
| 8 | 12321 |
| 9 | 14641 |
| 10 | 20502 |
| 11 | 23632 |
| 12 | 26962 |
| 13 | 40804 |
| 14 | 44944 |
| 15 | 1002001 |
| 16 | 1113111 |
| 17 | 1226221 |
| 18 | 1234321 |
| 19 | 1357531 |
| 20 | 2005002 |
| 21 | 2126212 |
| 22 | 2216122 |
| 23 | 2249422 |
| 24 | 2347432 |
| 25 | 2429242 |
| 26 | 4008004 |
| 27 | 4229224 |
| 28 | 100020001 |
[0,1,4,9,121,252,484,10201,12321,14641,20502, 23632,26962,40804,44944,1002001,1113111,1226221, 1234321,1357531,2005002,2126212,2216122,2249422, 2347432,2429242,4008004,4229224,100020001] |