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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 25 |
| 5 | 121 |
| 6 | 361 |
| 7 | 841 |
| 8 | 4201 |
| 9 | 25705 |
| 10 | 118441 |
| 11 | 423721 |
| 12 | 1628881 |
| 13 | 8065201 |
| 14 | 41225185 |
| 15 | 184416961 |
| 16 | 768211081 |
| 17 | 3420474121 |
| 18 | 16620237001 |
| 19 | 79922011465 |
| 20 | 364149052705 |
| 21 | 1638806098945 |
| 22 | 7655390077105 |
| 23 | 36739991161105 |
| 24 | 174363209490625 |
| 25 | 811840219629121 |
| 26 | 3790118889635521 |
[1,1,1,1,25,121,361,841,4201,25705,118441,423721, 1628881,8065201,41225185,184416961,768211081, 3420474121,16620237001,79922011465,364149052705, 1638806098945,7655390077105,36739991161105, 174363209490625,811840219629121,3790118889635521] |