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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 6470 |
| 3 | 245157 |
| 4 | 2630044 |
| 5 | 15380937 |
| 6 | 62893270 |
| 7 | 202927725 |
| 8 | 553275192 |
| 9 | 1329890705 |
| 10 | 2898762854 |
| 11 | 5843355957 |
| 12 | 11050100956 |
| 13 | 19813501785 |
| 14 | 33963673590 |
| 15 | 56017460733 |
| 16 | 89356455544 |
| 17 | 138432467745 |
| 18 | 209004466054 |
| 19 | 308406729925 |
| 20 | 445853163548 |
| 21 | 632776453353 |
| 22 | 883208213270 |
[0,1,6470,245157,2630044,15380937,62893270, 202927725,553275192,1329890705,2898762854, 5843355957,11050100956,19813501785,33963673590, 56017460733,89356455544,138432467745,209004466054, 308406729925,445853163548,632776453353, 883208213270] |