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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 272 |
| 3 | 256 |
| 4 | 2130 |
| 5 | 5060 |
| 6 | 26577 |
| 7 | 96739 |
| 8 | 437098 |
| 9 | 1790654 |
| 10 | 7846313 |
| 11 | 33489668 |
| 12 | 146020567 |
| 13 | 632928299 |
| 14 | 2759573954 |
| 15 | 12031721087 |
| 16 | 52517794501 |
| 17 | 229550541255 |
| 18 | 1003154198402 |
| 19 | 4390141774803 |
| 20 | 19203048654511 |
| 21 | 84095708519850 |
[1,272,256,2130,5060,26577,96739,437098,1790654, 7846313,33489668,146020567,632928299,2759573954, 12031721087,52517794501,229550541255, 1003154198402,4390141774803,19203048654511, 84095708519850] |