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| n | a(n) |
|---|---|
| 1 | 28 |
| 2 | 418 |
| 3 | 2485 |
| 4 | 9605 |
| 5 | 28700 |
| 6 | 72128 |
| 7 | 159978 |
| 8 | 322770 |
| 9 | 604560 |
| 10 | 1066450 |
| 11 | 1790503 |
| 12 | 2884063 |
| 13 | 4484480 |
| 14 | 6764240 |
| 15 | 9936500 |
| 16 | 14261028 |
| 17 | 20050548 |
| 18 | 27677490 |
| 19 | 37581145 |
| 20 | 50275225 |
| 21 | 66355828 |
| 22 | 86509808 |
| 23 | 111523550 |
| 24 | 142292150 |
| 25 | 179829000 |
| 26 | 225275778 |
[28,418,2485,9605,28700,72128,159978,322770, 604560,1066450,1790503,2884063,4484480,6764240, 9936500,14261028,20050548,27677490,37581145, 50275225,66355828,86509808,111523550,142292150, 179829000,225275778] |