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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 11 |
| 4 | 25 |
| 5 | 55 |
| 6 | 120 |
| 7 | 258 |
| 8 | 551 |
| 9 | 1169 |
| 10 | 2469 |
| 11 | 5193 |
| 12 | 10885 |
| 13 | 22746 |
| 14 | 47404 |
| 15 | 98553 |
| 16 | 204443 |
| 17 | 423259 |
| 18 | 874680 |
| 19 | 1804556 |
| 20 | 3717348 |
| 21 | 7647075 |
| 22 | 15711194 |
| 23 | 32242013 |
| 24 | 66096274 |
| 25 | 135366764 |
| 26 | 276988466 |
| 27 | 566312984 |
| 28 | 1156974619 |
| 29 | 2362043602 |
[1,2,5,11,25,55,120,258,551,1169,2469,5193,10885, 22746,47404,98553,204443,423259,874680,1804556, 3717348,7647075,15711194,32242013,66096274, 135366764,276988466,566312984,1156974619, 2362043602] |