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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 16 |
| 3 | 45 |
| 4 | 117 |
| 5 | 291 |
| 6 | 700 |
| 7 | 1646 |
| 8 | 3799 |
| 9 | 8647 |
| 10 | 19448 |
| 11 | 43330 |
| 12 | 95738 |
| 13 | 210094 |
| 14 | 458216 |
| 15 | 994204 |
| 16 | 2146955 |
| 17 | 4617439 |
| 18 | 9893376 |
| 19 | 21128058 |
| 20 | 44982486 |
| 21 | 95510090 |
| 22 | 202278376 |
| 23 | 427425860 |
| 24 | 901236582 |
| 25 | 1896594966 |
| 26 | 3983929680 |
| 27 | 8354539156 |
| 28 | 17492095604 |
[1,5,16,45,117,291,700,1646,3799,8647,19448,43330, 95738,210094,458216,994204,2146955,4617439, 9893376,21128058,44982486,95510090,202278376, 427425860,901236582,1896594966,3983929680, 8354539156,17492095604] |