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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 35 |
| 2 | 405 |
| 3 | 2695 |
| 4 | 12740 |
| 5 | 47628 |
| 6 | 149940 |
| 7 | 413820 |
| 8 | 1029105 |
| 9 | 2351635 |
| 10 | 5010005 |
| 11 | 10061415 |
| 12 | 19211920 |
| 13 | 35119280 |
| 14 | 61799760 |
| 15 | 105163632 |
| 16 | 173707785 |
| 17 | 279397755 |
| 18 | 438775645 |
| 19 | 674334815 |
| 20 | 1016206884 |
| 21 | 1504211500 |
| 22 | 2190324500 |
| 23 | 3141625500 |
| 24 | 4443791625 |
| 25 | 6205210011 |
| 26 | 8561787885 |
[1,35,405,2695,12740,47628,149940,413820,1029105, 2351635,5010005,10061415,19211920,35119280, 61799760,105163632,173707785,279397755,438775645, 674334815,1016206884,1504211500,2190324500, 3141625500,4443791625,6205210011,8561787885] |