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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 12 |
| 3 | 49 |
| 4 | 219 |
| 5 | 971 |
| 6 | 4517 |
| 7 | 20771 |
| 8 | 98450 |
| 9 | 461981 |
| 10 | 2213354 |
| 11 | 10519245 |
| 12 | 50753596 |
| 13 | 243307767 |
| 14 | 1179762984 |
| 15 | 5690972110 |
| 16 | 27696647862 |
| 17 | 134229569535 |
| 18 | 655129908566 |
| 19 | 3186566575192 |
| 20 | 15587994181738 |
| 21 | 76039623155226 |
| 22 | 372662021788428 |
| 23 | 1822155305407466 |
| 24 | 8944059110331015 |
| 25 | 43817771192888596 |
| 26 | 215363155240618719 |
[1,3,12,49,219,971,4517,20771,98450,461981, 2213354,10519245,50753596,243307767,1179762984, 5690972110,27696647862,134229569535,655129908566, 3186566575192,15587994181738,76039623155226, 372662021788428,1822155305407466,8944059110331015, 43817771192888596,215363155240618719] |