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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 12 |
| 3 | 41 |
| 4 | 141 |
| 5 | 482 |
| 6 | 1651 |
| 7 | 5653 |
| 8 | 19356 |
| 9 | 66277 |
| 10 | 226937 |
| 11 | 777050 |
| 12 | 2660679 |
| 13 | 9110369 |
| 14 | 31194604 |
| 15 | 106812721 |
| 16 | 365734965 |
| 17 | 1252304626 |
| 18 | 4287987275 |
| 19 | 14682397949 |
| 20 | 50273658876 |
| 21 | 172140871373 |
| 22 | 589423572097 |
| 23 | 2018231606314 |
| 24 | 6910580115135 |
[4,12,41,141,482,1651,5653,19356,66277,226937, 777050,2660679,9110369,31194604,106812721, 365734965,1252304626,4287987275,14682397949, 50273658876,172140871373,589423572097, 2018231606314,6910580115135] |