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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 21 |
| 5 | 73 |
| 6 | 228 |
| 7 | 616 |
| 8 | 1460 |
| 9 | 3110 |
| 10 | 6082 |
| 11 | 11102 |
| 12 | 19155 |
| 13 | 31539 |
| 14 | 49924 |
| 15 | 76416 |
| 16 | 113626 |
| 17 | 164744 |
| 18 | 233618 |
| 19 | 324838 |
| 20 | 443825 |
| 21 | 596925 |
| 22 | 791508 |
| 23 | 1036072 |
| 24 | 1340352 |
| 25 | 1715434 |
| 26 | 2173874 |
| 27 | 2729822 |
| 28 | 3399151 |
| 29 | 4199591 |
| 30 | 5150868 |
[1,2,6,21,73,228,616,1460,3110,6082,11102,19155, 31539,49924,76416,113626,164744,233618,324838, 443825,596925,791508,1036072,1340352,1715434, 2173874,2729822,3399151,4199591,5150868] |