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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 16 |
| 3 | 48 |
| 4 | 118 |
| 5 | 255 |
| 6 | 503 |
| 7 | 926 |
| 8 | 1614 |
| 9 | 2690 |
| 10 | 4318 |
| 11 | 6712 |
| 12 | 10146 |
| 13 | 14965 |
| 14 | 21597 |
| 15 | 30566 |
| 16 | 42506 |
| 17 | 58176 |
| 18 | 78476 |
| 19 | 104464 |
| 20 | 137374 |
| 21 | 178635 |
| 22 | 229891 |
| 23 | 293022 |
| 24 | 370166 |
| 25 | 463742 |
| 26 | 576474 |
| 27 | 711416 |
| 28 | 871978 |
| 29 | 1061953 |
| 30 | 1285545 |
| 31 | 1547398 |
| 32 | 1852626 |
| 33 | 2206844 |
| 34 | 2616200 |
[4,16,48,118,255,503,926,1614,2690,4318,6712, 10146,14965,21597,30566,42506,58176,78476,104464, 137374,178635,229891,293022,370166,463742,576474, 711416,871978,1061953,1285545,1547398,1852626, 2206844,2616200] |