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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 23 |
| 5 | 66 |
| 6 | 225 |
| 7 | 760 |
| 8 | 2635 |
| 9 | 9326 |
| 10 | 34170 |
| 11 | 125303 |
| 12 | 465172 |
| 13 | 1760793 |
| 14 | 6717459 |
| 15 | 25686249 |
| 16 | 99508522 |
| 17 | 388671862 |
| 18 | 1520793455 |
| 19 | 5988924457 |
| 20 | 23774733713 |
| 21 | 94606934110 |
| 22 | 377603437450 |
| 23 | 1516510098070 |
| 24 | 6110962006800 |
| 25 | 24665305422044 |
| 26 | 99964889907241 |
| 27 | 406640072920187 |
| 28 | 1656607435261793 |
| 29 | 6765556140331184 |
[1,1,3,7,23,66,225,760,2635,9326,34170,125303, 465172,1760793,6717459,25686249,99508522, 388671862,1520793455,5988924457,23774733713, 94606934110,377603437450,1516510098070, 6110962006800,24665305422044,99964889907241, 406640072920187,1656607435261793,6765556140331184] |