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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 10 |
| 4 | 34 |
| 5 | 101 |
| 6 | 331 |
| 7 | 1044 |
| 8 | 3406 |
| 9 | 11008 |
| 10 | 36039 |
| 11 | 117866 |
| 12 | 387709 |
| 13 | 1276783 |
| 14 | 4217763 |
| 15 | 13954040 |
| 16 | 46258390 |
| 17 | 153562565 |
| 18 | 510523621 |
| 19 | 1699272620 |
| 20 | 5662498639 |
| 21 | 18888082230 |
| 22 | 63062936820 |
| 23 | 210730527620 |
| 24 | 704727803329 |
| 25 | 2358457291626 |
| 26 | 7898146040191 |
[1,4,10,34,101,331,1044,3406,11008,36039,117866, 387709,1276783,4217763,13954040,46258390, 153562565,510523621,1699272620,5662498639, 18888082230,63062936820,210730527620,704727803329, 2358457291626,7898146040191] |