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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 8 |
| 4 | 26 |
| 5 | 92 |
| 6 | 360 |
| 7 | 1416 |
| 8 | 5698 |
| 9 | 23513 |
| 10 | 98346 |
| 11 | 416418 |
| 12 | 1783144 |
| 13 | 7704322 |
| 14 | 33546344 |
| 15 | 147071592 |
| 16 | 648636050 |
| 17 | 2875822121 |
| 18 | 12810531924 |
| 19 | 57306505152 |
| 20 | 257330920910 |
| 21 | 1159517118330 |
| 22 | 5241137123470 |
| 23 | 23758569938458 |
| 24 | 107983949179512 |
| 25 | 491985193384077 |
| 26 | 2246564114646650 |
[1,1,2,8,26,92,360,1416,5698,23513,98346,416418, 1783144,7704322,33546344,147071592,648636050, 2875822121,12810531924,57306505152,257330920910, 1159517118330,5241137123470,23758569938458, 107983949179512,491985193384077,2246564114646650] |