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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 36 |
| 3 | 78 |
| 4 | 171 |
| 5 | 406 |
| 6 | 990 |
| 7 | 2485 |
| 8 | 6328 |
| 9 | 16290 |
| 10 | 42195 |
| 11 | 109746 |
| 12 | 286146 |
| 13 | 747253 |
| 14 | 1953276 |
| 15 | 5108806 |
| 16 | 13367035 |
| 17 | 34982430 |
| 18 | 91564278 |
| 19 | 239684565 |
| 20 | 627447600 |
| 21 | 1642590586 |
| 22 | 4300214691 |
| 23 | 11257876378 |
| 24 | 29473127866 |
| 25 | 77161043541 |
| 26 | 202009252500 |
[6,36,78,171,406,990,2485,6328,16290,42195,109746, 286146,747253,1953276,5108806,13367035,34982430, 91564278,239684565,627447600,1642590586, 4300214691,11257876378,29473127866,77161043541, 202009252500] |