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| n | a(n) |
|---|---|
| 0 | 4 |
| 1 | 7 |
| 2 | 12 |
| 3 | 15 |
| 4 | 28 |
| 5 | 55 |
| 6 | 72 |
| 7 | 147 |
| 8 | 304 |
| 9 | 403 |
| 10 | 840 |
| 11 | 1755 |
| 12 | 2332 |
| 13 | 4879 |
| 14 | 10212 |
| 15 | 13575 |
| 16 | 28420 |
| 17 | 59503 |
| 18 | 79104 |
| 19 | 165627 |
| 20 | 346792 |
| 21 | 461035 |
| 22 | 965328 |
| 23 | 2021235 |
| 24 | 2687092 |
| 25 | 5626327 |
| 26 | 11780604 |
| 27 | 15661503 |
| 28 | 32792620 |
| 29 | 68662375 |
| 30 | 91281912 |
| 31 | 191129379 |
| 32 | 400193632 |
| 33 | 532029955 |
| 34 | 1113983640 |
[4,7,12,15,28,55,72,147,304,403,840,1755,2332, 4879,10212,13575,28420,59503,79104,165627,346792, 461035,965328,2021235,2687092,5626327,11780604, 15661503,32792620,68662375,91281912,191129379, 400193632,532029955,1113983640] |