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| n | a(n) |
|---|---|
| 1 | 16 |
| 2 | 48 |
| 3 | 141 |
| 4 | 378 |
| 5 | 988 |
| 6 | 2482 |
| 7 | 6109 |
| 8 | 14712 |
| 9 | 34896 |
| 10 | 81612 |
| 11 | 188725 |
| 12 | 432046 |
| 13 | 980620 |
| 14 | 2208798 |
| 15 | 4941909 |
| 16 | 10990620 |
| 17 | 24311440 |
| 18 | 53516200 |
| 19 | 117285181 |
| 20 | 256007874 |
| 21 | 556755036 |
| 22 | 1206716778 |
| 23 | 2607303661 |
| 24 | 5617260448 |
| 25 | 12069653488 |
| 26 | 25869224292 |
[16,48,141,378,988,2482,6109,14712,34896,81612, 188725,432046,980620,2208798,4941909,10990620, 24311440,53516200,117285181,256007874,556755036, 1206716778,2607303661,5617260448,12069653488, 25869224292] |