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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 19 |
| 4 | 74 |
| 5 | 248 |
| 6 | 814 |
| 7 | 2457 |
| 8 | 7168 |
| 9 | 19928 |
| 10 | 53688 |
| 11 | 139820 |
| 12 | 354987 |
| 13 | 878434 |
| 14 | 2128102 |
| 15 | 5052010 |
| 16 | 11781881 |
| 17 | 27019758 |
| 18 | 61035671 |
| 19 | 135928105 |
| 20 | 298784144 |
| 21 | 648726349 |
| 22 | 1392474574 |
| 23 | 2956730910 |
| 24 | 6214668074 |
| 25 | 12937060340 |
| 26 | 26686392239 |
| 27 | 54572423946 |
| 28 | 110680119454 |
| 29 | 222710856175 |
| 30 | 444776676764 |
[1,1,5,19,74,248,814,2457,7168,19928,53688,139820, 354987,878434,2128102,5052010,11781881,27019758, 61035671,135928105,298784144,648726349,1392474574, 2956730910,6214668074,12937060340,26686392239, 54572423946,110680119454,222710856175, 444776676764] |