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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 9 |
| 4 | 16 |
| 5 | 39 |
| 6 | 67 |
| 7 | 157 |
| 8 | 264 |
| 9 | 623 |
| 10 | 1031 |
| 11 | 2555 |
| 12 | 4341 |
| 13 | 9836 |
| 14 | 16385 |
| 15 | 40958 |
| 16 | 69628 |
| 17 | 157689 |
| 18 | 263156 |
| 19 | 654827 |
| 20 | 1112793 |
| 21 | 2520832 |
| 22 | 4205311 |
| 23 | 10484863 |
| 24 | 17824575 |
| 25 | 40366239 |
| 26 | 67364591 |
| 27 | 167630935 |
| 28 | 284862387 |
| 29 | 645053197 |
| 30 | 1076334704 |
| 31 | 2684053423 |
| 32 | 4562656007 |
| 33 | 10333037691 |
[1,2,4,9,16,39,67,157,264,623,1031,2555,4341,9836, 16385,40958,69628,157689,263156,654827,1112793, 2520832,4205311,10484863,17824575,40366239, 67364591,167630935,284862387,645053197,1076334704, 2684053423,4562656007,10333037691] |