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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 23 |
| 6 | 64 |
| 7 | 134 |
| 8 | 373 |
| 9 | 781 |
| 10 | 2174 |
| 11 | 4552 |
| 12 | 12671 |
| 13 | 26531 |
| 14 | 73852 |
| 15 | 154634 |
| 16 | 430441 |
| 17 | 901273 |
| 18 | 2508794 |
| 19 | 5253004 |
| 20 | 14622323 |
| 21 | 30616751 |
| 22 | 85225144 |
| 23 | 178447502 |
| 24 | 496728541 |
| 25 | 1040068261 |
| 26 | 2895146102 |
| 27 | 6061962064 |
| 28 | 16874148071 |
| 29 | 35331704123 |
[1,1,2,4,11,23,64,134,373,781,2174,4552,12671, 26531,73852,154634,430441,901273,2508794,5253004, 14622323,30616751,85225144,178447502,496728541, 1040068261,2895146102,6061962064,16874148071, 35331704123] |