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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 43 |
| 6 | 147 |
| 7 | 521 |
| 8 | 1941 |
| 9 | 7480 |
| 10 | 29589 |
| 11 | 119739 |
| 12 | 493859 |
| 13 | 2068429 |
| 14 | 8783152 |
| 15 | 37733105 |
| 16 | 163756225 |
| 17 | 717099427 |
| 18 | 3165207986 |
| 19 | 14069737107 |
| 20 | 62939441266 |
| 21 | 283160925349 |
| 22 | 1280508190885 |
| 23 | 5817930349391 |
| 24 | 26546802485592 |
| 25 | 121606719251131 |
| 26 | 559072059863772 |
| 27 | 2578817198577756 |
| 28 | 11931845796002335 |
[1,1,2,5,14,43,147,521,1941,7480,29589,119739, 493859,2068429,8783152,37733105,163756225, 717099427,3165207986,14069737107,62939441266, 283160925349,1280508190885,5817930349391, 26546802485592,121606719251131,559072059863772, 2578817198577756,11931845796002335] |