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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 4 |
| 2 | 15 |
| 3 | 37 |
| 4 | 87 |
| 5 | 172 |
| 6 | 322 |
| 7 | 574 |
| 8 | 995 |
| 9 | 1689 |
| 10 | 2827 |
| 11 | 4684 |
| 12 | 7719 |
| 13 | 12641 |
| 14 | 20648 |
| 15 | 33612 |
| 16 | 54620 |
| 17 | 88631 |
| 18 | 143691 |
| 19 | 232805 |
| 20 | 377024 |
| 21 | 610404 |
| 22 | 988052 |
| 23 | 1599131 |
| 24 | 2587911 |
| 25 | 4187825 |
| 26 | 6776576 |
| 27 | 10965300 |
| 28 | 17742836 |
| 29 | 28709159 |
| 30 | 46453083 |
| 31 | 75163397 |
| 32 | 121617704 |
| 33 | 196782431 |
| 34 | 318401539 |
[1,4,15,37,87,172,322,574,995,1689,2827,4684,7719, 12641,20648,33612,54620,88631,143691,232805, 377024,610404,988052,1599131,2587911,4187825, 6776576,10965300,17742836,28709159,46453083, 75163397,121617704,196782431,318401539] |