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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 32 |
| 6 | 113 |
| 7 | 422 |
| 8 | 1788 |
| 9 | 8015 |
| 10 | 39435 |
| 11 | 204910 |
| 12 | 1144377 |
| 13 | 6722107 |
| 14 | 41877722 |
| 15 | 273328660 |
| 16 | 1875326627 |
| 17 | 13427171644 |
| 18 | 100415636519 |
| 19 | 780856389454 |
| 20 | 6312398830812 |
| 21 | 52891894374481 |
| 22 | 459022366424253 |
| 23 | 4117482357137214 |
| 24 | 38140612800271305 |
| 25 | 364280428671552453 |
| 26 | 3584042687233836274 |
[1,1,2,4,11,32,113,422,1788,8015,39435,204910, 1144377,6722107,41877722,273328660,1875326627, 13427171644,100415636519,780856389454, 6312398830812,52891894374481,459022366424253, 4117482357137214,38140612800271305, 364280428671552453,3584042687233836274] |