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| n | a(n) |
|---|---|
| 0 | 5 |
| 1 | 41 |
| 2 | 189 |
| 3 | 645 |
| 4 | 1815 |
| 5 | 4455 |
| 6 | 9867 |
| 7 | 20163 |
| 8 | 38610 |
| 9 | 70070 |
| 10 | 121550 |
| 11 | 202878 |
| 12 | 327522 |
| 13 | 513570 |
| 14 | 784890 |
| 15 | 1172490 |
| 16 | 1716099 |
| 17 | 2465991 |
| 18 | 3485075 |
| 19 | 4851275 |
| 20 | 6660225 |
| 21 | 9028305 |
| 22 | 12096045 |
| 23 | 16031925 |
| 24 | 21036600 |
| 25 | 27347580 |
| 26 | 35244396 |
| 27 | 45054284 |
| 28 | 57158420 |
[5,41,189,645,1815,4455,9867,20163,38610,70070, 121550,202878,327522,513570,784890,1172490, 1716099,2465991,3485075,4851275,6660225,9028305, 12096045,16031925,21036600,27347580,35244396, 45054284,57158420] |