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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 16 |
| 5 | 42 |
| 6 | 147 |
| 7 | 454 |
| 8 | 1628 |
| 9 | 5425 |
| 10 | 20178 |
| 11 | 70153 |
| 12 | 268235 |
| 13 | 963094 |
| 14 | 3750168 |
| 15 | 13820410 |
| 16 | 54545612 |
| 17 | 205188861 |
| 18 | 818752204 |
| 19 | 3130596415 |
| 20 | 12607433542 |
| 21 | 48850200688 |
| 22 | 198265158766 |
| 23 | 776800033465 |
| 24 | 3173598172091 |
| 25 | 12552548689917 |
| 26 | 51573263660315 |
| 27 | 205664370031343 |
| 28 | 849144348277944 |
| 29 | 3410421662866518 |
[1,1,2,5,16,42,147,454,1628,5425,20178,70153, 268235,963094,3750168,13820410,54545612,205188861, 818752204,3130596415,12607433542,48850200688, 198265158766,776800033465,3173598172091, 12552548689917,51573263660315,205664370031343, 849144348277944,3410421662866518] |