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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 2 |
| 6 | 4 |
| 7 | 6 |
| 8 | 11 |
| 9 | 18 |
| 10 | 37 |
| 11 | 66 |
| 12 | 135 |
| 13 | 265 |
| 14 | 552 |
| 15 | 1132 |
| 16 | 2410 |
| 17 | 5098 |
| 18 | 11020 |
| 19 | 23846 |
| 20 | 52233 |
| 21 | 114796 |
| 22 | 254371 |
| 23 | 565734 |
| 24 | 1265579 |
| 25 | 2841632 |
| 26 | 6408674 |
| 27 | 14502229 |
| 28 | 32935002 |
| 29 | 75021750 |
| 30 | 171404424 |
| 31 | 392658842 |
| 32 | 901842517 |
| 33 | 2076217086 |
| 34 | 4790669518 |
| 35 | 11077270335 |
[1,1,1,1,2,2,4,6,11,18,37,66,135,265,552,1132, 2410,5098,11020,23846,52233,114796,254371,565734, 1265579,2841632,6408674,14502229,32935002, 75021750,171404424,392658842,901842517,2076217086, 4790669518,11077270335] |