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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 7 |
| 3 | 19 |
| 4 | 49 |
| 5 | 127 |
| 6 | 327 |
| 7 | 841 |
| 8 | 2157 |
| 9 | 5523 |
| 10 | 14115 |
| 11 | 36019 |
| 12 | 91779 |
| 13 | 233557 |
| 14 | 593625 |
| 15 | 1507125 |
| 16 | 3822395 |
| 17 | 9685135 |
| 18 | 24518103 |
| 19 | 62016309 |
| 20 | 156742115 |
| 21 | 395865603 |
| 22 | 999105203 |
| 23 | 2519960799 |
| 24 | 6352014717 |
| 25 | 16002180569 |
| 26 | 40291214021 |
| 27 | 101395244925 |
| 28 | 255042422247 |
[1,3,7,19,49,127,327,841,2157,5523,14115,36019, 91779,233557,593625,1507125,3822395,9685135, 24518103,62016309,156742115,395865603,999105203, 2519960799,6352014717,16002180569,40291214021, 101395244925,255042422247] |