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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 13 |
| 4 | 59 |
| 5 | 193 |
| 6 | 895 |
| 7 | 3259 |
| 8 | 15359 |
| 9 | 58873 |
| 10 | 280173 |
| 11 | 1113879 |
| 12 | 5348147 |
| 13 | 21804729 |
| 14 | 105287385 |
| 15 | 437178569 |
| 16 | 2120520381 |
| 17 | 8935434007 |
| 18 | 43498711149 |
| 19 | 185440154245 |
| 20 | 905220919951 |
| 21 | 3896089055715 |
| 22 | 19062269002521 |
| 23 | 82711407198491 |
| 24 | 405451224884227 |
| 25 | 1771346414264423 |
| 26 | 8696751070014109 |
| 27 | 38219970873869521 |
[1,1,5,13,59,193,895,3259,15359,58873,280173, 1113879,5348147,21804729,105287385,437178569, 2120520381,8935434007,43498711149,185440154245, 905220919951,3896089055715,19062269002521, 82711407198491,405451224884227,1771346414264423, 8696751070014109,38219970873869521] |