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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 19 |
| 3 | 68 |
| 4 | 207 |
| 5 | 997 |
| 6 | 4210 |
| 7 | 16658 |
| 8 | 68769 |
| 9 | 284867 |
| 10 | 1170146 |
| 11 | 4807394 |
| 12 | 19787328 |
| 13 | 81424284 |
| 14 | 334903296 |
| 15 | 1377738399 |
| 16 | 5668140481 |
| 17 | 23317788357 |
| 18 | 95926011656 |
| 19 | 394630220291 |
| 20 | 1623463820564 |
| 21 | 6678736090662 |
| 22 | 27475550500449 |
| 23 | 113031264492453 |
[1,19,68,207,997,4210,16658,68769,284867,1170146, 4807394,19787328,81424284,334903296,1377738399, 5668140481,23317788357,95926011656,394630220291, 1623463820564,6678736090662,27475550500449, 113031264492453] |