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| n | a(n) |
|---|---|
| 1 | 16 |
| 2 | 48 |
| 3 | 124 |
| 4 | 294 |
| 5 | 680 |
| 6 | 1578 |
| 7 | 3600 |
| 8 | 8458 |
| 9 | 19460 |
| 10 | 46510 |
| 11 | 108280 |
| 12 | 262542 |
| 13 | 617264 |
| 14 | 1512270 |
| 15 | 3580596 |
| 16 | 8834026 |
| 17 | 21015224 |
| 18 | 52087762 |
| 19 | 124294096 |
| 20 | 308994090 |
| 21 | 738810308 |
| 22 | 1840241022 |
| 23 | 4405749912 |
| 24 | 10987766974 |
| 25 | 26328139088 |
| 26 | 65715472894 |
| 27 | 157549520692 |
[16,48,124,294,680,1578,3600,8458,19460,46510, 108280,262542,617264,1512270,3580596,8834026, 21015224,52087762,124294096,308994090,738810308, 1840241022,4405749912,10987766974,26328139088, 65715472894,157549520692] |