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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 22 |
| 5 | 86 |
| 6 | 338 |
| 7 | 1314 |
| 8 | 5046 |
| 9 | 19190 |
| 10 | 72482 |
| 11 | 272530 |
| 12 | 1021734 |
| 13 | 3823622 |
| 14 | 14293234 |
| 15 | 53394370 |
| 16 | 199382550 |
| 17 | 744348822 |
| 18 | 2778471490 |
| 19 | 10370520178 |
| 20 | 38705706374 |
| 21 | 144456761766 |
| 22 | 539130777874 |
| 23 | 2012086272674 |
| 24 | 7509256255862 |
| 25 | 28025026831158 |
| 26 | 104591035618146 |
[1,1,2,6,22,86,338,1314,5046,19190,72482,272530, 1021734,3823622,14293234,53394370,199382550, 744348822,2778471490,10370520178,38705706374, 144456761766,539130777874,2012086272674, 7509256255862,28025026831158,104591035618146] |