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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 45 |
| 2 | 825 |
| 3 | 9075 |
| 4 | 70785 |
| 5 | 429429 |
| 6 | 2147145 |
| 7 | 9202050 |
| 8 | 34763300 |
| 9 | 118195220 |
| 10 | 367479684 |
| 11 | 1057896060 |
| 12 | 2848181700 |
| 13 | 7229999700 |
| 14 | 17420856420 |
| 15 | 40067969766 |
| 16 | 88385227425 |
| 17 | 187746398125 |
| 18 | 385374185625 |
| 19 | 766691800875 |
| 20 | 1482270815025 |
| 21 | 2791289197125 |
| 22 | 5130235085625 |
| 23 | 9219552907500 |
[1,45,825,9075,70785,429429,2147145,9202050, 34763300,118195220,367479684,1057896060, 2848181700,7229999700,17420856420,40067969766, 88385227425,187746398125,385374185625, 766691800875,1482270815025,2791289197125, 5130235085625,9219552907500] |