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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 13 |
| 4 | 68 |
| 5 | 358 |
| 6 | 1871 |
| 7 | 9757 |
| 8 | 50825 |
| 9 | 264622 |
| 10 | 1377455 |
| 11 | 7169434 |
| 12 | 37314044 |
| 13 | 194200651 |
| 14 | 1010706167 |
| 15 | 5260139653 |
| 16 | 27375923678 |
| 17 | 142475405353 |
| 18 | 741499470476 |
| 19 | 3859061584762 |
| 20 | 20084107492055 |
| 21 | 104525763472957 |
| 22 | 543994053280925 |
| 23 | 2831163512738434 |
| 24 | 14734511818610939 |
[1,2,13,68,358,1871,9757,50825,264622,1377455, 7169434,37314044,194200651,1010706167,5260139653, 27375923678,142475405353,741499470476, 3859061584762,20084107492055,104525763472957, 543994053280925,2831163512738434, 14734511818610939] |