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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 26 |
| 5 | 80 |
| 6 | 277 |
| 7 | 930 |
| 8 | 3318 |
| 9 | 11643 |
| 10 | 42412 |
| 11 | 152958 |
| 12 | 565237 |
| 13 | 2075930 |
| 14 | 7753263 |
| 15 | 28843854 |
| 16 | 108607503 |
| 17 | 407906636 |
| 18 | 1545829275 |
| 19 | 5848333453 |
| 20 | 22278963147 |
| 21 | 84775245709 |
| 22 | 324339392219 |
| 23 | 1239936468371 |
| 24 | 4760994836197 |
| 25 | 18271315079302 |
| 26 | 70372359435245 |
| 27 | 270943377363634 |
| 28 | 1046308088337600 |
| 29 | 4039544714639796 |
[1,1,3,8,26,80,277,930,3318,11643,42412,152958, 565237,2075930,7753263,28843854,108607503, 407906636,1545829275,5848333453,22278963147, 84775245709,324339392219,1239936468371, 4760994836197,18271315079302,70372359435245, 270943377363634,1046308088337600,4039544714639796] |