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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 28 |
| 2 | 533 |
| 3 | 8648 |
| 4 | 128889 |
| 5 | 1824276 |
| 6 | 24950461 |
| 7 | 333078016 |
| 8 | 4367420897 |
| 9 | 56484732044 |
| 10 | 722650676709 |
| 11 | 9164986526904 |
| 12 | 115404823162825 |
| 13 | 1444532800672132 |
| 14 | 17990818115880077 |
| 15 | 223110488408176112 |
[1,28,533,8648,128889,1824276,24950461,333078016, 4367420897,56484732044,722650676709,9164986526904, 115404823162825,1444532800672132, 17990818115880077,223110488408176112] |