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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 13 |
| 3 | 55 |
| 4 | 249 |
| 5 | 1131 |
| 6 | 5253 |
| 7 | 24543 |
| 8 | 115825 |
| 9 | 549331 |
| 10 | 2620029 |
| 11 | 12543367 |
| 12 | 60270697 |
| 13 | 290423355 |
| 14 | 1403088885 |
| 15 | 6793370415 |
| 16 | 32956254945 |
| 17 | 160152588195 |
| 18 | 779470975725 |
| 19 | 3798948989655 |
| 20 | 18538237315545 |
| 21 | 90565618791435 |
| 22 | 442899758973285 |
| 23 | 2167985089576575 |
| 24 | 10621425660150609 |
| 25 | 52078139149834611 |
| 26 | 255533719072119133 |
[1,3,13,55,249,1131,5253,24543,115825,549331, 2620029,12543367,60270697,290423355,1403088885, 6793370415,32956254945,160152588195,779470975725, 3798948989655,18538237315545,90565618791435, 442899758973285,2167985089576575, 10621425660150609,52078139149834611, 255533719072119133] |