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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 4 |
| 5 | 6 |
| 6 | 8 |
| 7 | 18 |
| 8 | 20 |
| 9 | 56 |
| 10 | 48 |
| 11 | 178 |
| 12 | 132 |
| 13 | 574 |
| 14 | 348 |
| 15 | 1870 |
| 16 | 1008 |
| 17 | 6144 |
| 18 | 2812 |
| 19 | 20314 |
| 20 | 8420 |
| 21 | 67534 |
| 22 | 24396 |
| 23 | 225472 |
| 24 | 74756 |
| 25 | 755672 |
| 26 | 222556 |
| 27 | 2540406 |
| 28 | 693692 |
| 29 | 8564622 |
| 30 | 2107748 |
| 31 | 28941258 |
| 32 | 6656376 |
| 33 | 98011464 |
| 34 | 20548932 |
[1,2,2,4,6,8,18,20,56,48,178,132,574,348,1870, 1008,6144,2812,20314,8420,67534,24396,225472, 74756,755672,222556,2540406,693692,8564622, 2107748,28941258,6656376,98011464,20548932] |