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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 345 |
| 3 | 2509 |
| 4 | 11107 |
| 5 | 36569 |
| 6 | 99143 |
| 7 | 232969 |
| 8 | 492307 |
| 9 | 958025 |
| 10 | 1743993 |
| 11 | 3006947 |
| 12 | 4955757 |
| 13 | 7859017 |
| 14 | 12059931 |
| 15 | 17987847 |
| 16 | 26166137 |
| 17 | 37233755 |
| 18 | 51958111 |
| 19 | 71242519 |
| 20 | 96156041 |
| 21 | 127946965 |
| 22 | 168048881 |
| 23 | 218120357 |
| 24 | 280058879 |
| 25 | 356003167 |
| 26 | 448386363 |
[21,345,2509,11107,36569,99143,232969,492307, 958025,1743993,3006947,4955757,7859017,12059931, 17987847,26166137,37233755,51958111,71242519, 96156041,127946965,168048881,218120357,280058879, 356003167,448386363] |