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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 8 |
| 3 | 22 |
| 4 | 62 |
| 5 | 178 |
| 6 | 519 |
| 7 | 1533 |
| 8 | 4578 |
| 9 | 13800 |
| 10 | 41937 |
| 11 | 128345 |
| 12 | 395232 |
| 13 | 1223792 |
| 14 | 3807903 |
| 15 | 11900549 |
| 16 | 37339043 |
| 17 | 117574429 |
| 18 | 371429284 |
| 19 | 1176876762 |
| 20 | 3739129185 |
| 21 | 11909686261 |
| 22 | 38022182028 |
| 23 | 121648373964 |
| 24 | 389979453010 |
| 25 | 1252517211660 |
| 26 | 4029754366713 |
| 27 | 12986073134365 |
[1,3,8,22,62,178,519,1533,4578,13800,41937,128345, 395232,1223792,3807903,11900549,37339043, 117574429,371429284,1176876762,3739129185, 11909686261,38022182028,121648373964,389979453010, 1252517211660,4029754366713,12986073134365] |