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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 13 |
| 4 | 42 |
| 5 | 138 |
| 6 | 482 |
| 7 | 1654 |
| 8 | 6153 |
| 9 | 22665 |
| 10 | 86602 |
| 11 | 325298 |
| 12 | 1282358 |
| 13 | 4990247 |
| 14 | 19921217 |
| 15 | 78358303 |
| 16 | 318886120 |
| 17 | 1281888719 |
| 18 | 5254017106 |
| 19 | 21261292818 |
| 20 | 88301518722 |
| 21 | 362702052232 |
| 22 | 1513168885596 |
| 23 | 6243268426298 |
| 24 | 26300445746536 |
| 25 | 109710928573843 |
| 26 | 463595936683840 |
| 27 | 1940069540427649 |
| 28 | 8259430332344895 |
[1,2,5,13,42,138,482,1654,6153,22665,86602,325298, 1282358,4990247,19921217,78358303,318886120, 1281888719,5254017106,21261292818,88301518722, 362702052232,1513168885596,6243268426298, 26300445746536,109710928573843,463595936683840, 1940069540427649,8259430332344895] |