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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 13 |
| 2 | 90 |
| 3 | 553 |
| 4 | 2376 |
| 5 | 8064 |
| 6 | 25771 |
| 7 | 70603 |
| 8 | 172012 |
| 9 | 405175 |
| 10 | 875990 |
| 11 | 1765534 |
| 12 | 3484228 |
| 13 | 6508702 |
| 14 | 11604117 |
| 15 | 20390870 |
| 16 | 34490146 |
| 17 | 56425254 |
| 18 | 91343551 |
| 19 | 143775379 |
| 20 | 220716013 |
| 21 | 336122564 |
| 22 | 500966646 |
| 23 | 732267501 |
| 24 | 1063633842 |
| 25 | 1518831488 |
[1,13,90,553,2376,8064,25771,70603,172012,405175, 875990,1765534,3484228,6508702,11604117,20390870, 34490146,56425254,91343551,143775379,220716013, 336122564,500966646,732267501,1063633842, 1518831488] |