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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 21 |
| 3 | 84 |
| 4 | 233 |
| 5 | 550 |
| 6 | 1188 |
| 7 | 2415 |
| 8 | 4684 |
| 9 | 8746 |
| 10 | 15833 |
| 11 | 27945 |
| 12 | 48286 |
| 13 | 81907 |
| 14 | 136629 |
| 15 | 224336 |
| 16 | 362747 |
| 17 | 577797 |
| 18 | 906780 |
| 19 | 1402432 |
| 20 | 2138159 |
| 21 | 3214644 |
| 22 | 4768098 |
| 23 | 6980453 |
| 24 | 10091830 |
| 25 | 14415652 |
| 26 | 20356811 |
| 27 | 28433339 |
| 28 | 39302076 |
| 29 | 53788873 |
| 30 | 72923915 |
| 31 | 97982798 |
[6,21,84,233,550,1188,2415,4684,8746,15833,27945, 48286,81907,136629,224336,362747,577797,906780, 1402432,2138159,3214644,4768098,6980453,10091830, 14415652,20356811,28433339,39302076,53788873, 72923915,97982798] |