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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 24 |
| 5 | 76 |
| 6 | 277 |
| 7 | 1012 |
| 8 | 3900 |
| 9 | 15298 |
| 10 | 61744 |
| 11 | 252844 |
| 12 | 1055394 |
| 13 | 4456946 |
| 14 | 19066780 |
| 15 | 82383168 |
| 16 | 359267491 |
| 17 | 1579448039 |
| 18 | 6994656090 |
| 19 | 31175776248 |
| 20 | 139782570970 |
| 21 | 630064954347 |
| 22 | 2853843406073 |
| 23 | 12983914841969 |
| 24 | 59312608158319 |
| 25 | 271967699137691 |
| 26 | 1251392188397235 |
| 27 | 5776438662674473 |
| 28 | 26743675660270307 |
[1,1,3,7,24,76,277,1012,3900,15298,61744,252844, 1055394,4456946,19066780,82383168,359267491, 1579448039,6994656090,31175776248,139782570970, 630064954347,2853843406073,12983914841969, 59312608158319,271967699137691,1251392188397235, 5776438662674473,26743675660270307] |